← JEE MAINS
JEE · combined subjects

JEE Main 2018 (15 Apr)

2018 · 90 questions · First 10 Solutions Free
Questions 1–10 have full step-by-step solutions visible. Sign in to unlock all 90 →
Q1 mcq
One mole of an ideal monatomic gas is compressed isothermally in a rigid vessel to double its pressure at room temperature, $27^{o}C$ . The magnitude of work done on the gas will be:
a.
$300R$
b.
$300Rln 2$ Correct Answer
c.
$300 ln 6$
d.
$300Rln 7$

No explanation saved for this question yet.

Q2 mcq
Light of wavelength $550\, nm$ falls normally on a slit of width $22.0 \times 10^{-5}\, cm$ . The angular position of the second minima from the central maximum will be (in radians):
a.
$\frac{\pi}{4}$
b.
$\frac{\pi}{8}$
c.
$\frac{\pi}{12}$
d.
$\frac{\pi}{6}$ Correct Answer

No explanation saved for this question yet.

Q3 mcq
A given object takes $n$ times more time to slide down a $45^{o}$ rough inclined plane as it takes to slide down a perfectly smooth $45^{o}$ incline. The coefficient of kinetic friction between the object and the incline is:
a.
$\sqrt{1} - \frac{1}{n^{2}}$
b.
$1 - \frac{1}{n^{2}}$ Correct Answer
c.
$\frac{1}{2-n^{2}}$
d.
$\sqrt{\,} \frac{1}{1-n^{2}}$

No explanation saved for this question yet.

Q4 mcq
A body of mass $m$ is moving in a circular orbit of radius $R$ about a planet of mass $M$ . At some instant, it splits into two equal masses. The first mass moves in a circular orbit of radius $\frac{R}{2}$ . And the other mass, in a circular orbit of radius $\frac{3R}{2}.$ The difference between the final and the initial total energies is
a.
$+ \frac{Gm}{6R}$
b.
$- \frac{Gm}{2R}$
c.
$- \frac{Gm}{6R}$ Correct Answer
d.
$\frac{Gm}{2R}$

No explanation saved for this question yet.

Q5 mcq
The relative error in the determination of the surface area of a sphere is $\alpha$ . The relative error in the determination of its volume is
a.
$\frac{3}{2}$ $\alpha$ Correct Answer
b.
$\frac{2}{3}$ $\alpha$
c.
$\alpha$
d.
$\frac{5}{2}$ $\alpha$

No explanation saved for this question yet.

Q6 mcq
Two electrons are moving with non-relativistic speeds perpendicular to each other. If corresponding de brogile wavelengths are $\lambda _{1}$ and $\lambda _{2}$ , their de brogile wavelength in the frame of reference attached to their centre of mass is:
a.
$\frac{1}{\lambda _{CM}} = \frac{1}{\lambda _{1}} + \frac{1}{\lambda _{2}}$
b.
$\lambda _{CM} = \frac{2\lambda _{1}\lambda _{2}}{\sqrt{\lambda ^{2}+\lambda ^{2}}}$ $1 2$ Correct Answer
c.
$\lambda _{CM} =\lambda _{1} =\lambda _{2}$
d.
$\lambda _{CM} = \frac{\lambda _{1}+\lambda _{2}}{2}$

No explanation saved for this question yet.

Q7 mcq
A Carnot's engine works like a refrigerator between $250\,K$ and $300\,K$ . It receives $500\, cal$ heat from the reservoir at a lower temperature. The amount of work done in each cycle to operate the refrigerator is,
a.
$772\,J$
b.
$420\,J$ Correct Answer
c.
$2100\,J$
d.
$2520\,J$

No explanation saved for this question yet.

Q8 mcq
A charge $Q$ is placed at a distance $^{a}/_{2}$ above the centre of a square surface of side length $a$ . The electric flux through the square surface due to the charge would be?
Question 8 image
a.
$\frac{Q}{6\epsilon _{0}}$ Correct Answer
b.
$\frac{Q}{2\epsilon _{0}}$
c.
$\frac{Q}{3\epsilon _{0}}$
d.
$\frac{Q}{\epsilon _{0}}$

No explanation saved for this question yet.

Q9 mcq
In a meter bridge as shown in the figure, it is given that resistance $Y = 12.5\,\Omega$ and that the balance is obtained at a distance $39. 5\, cm$ from end $A$ (by jockey $J$ ). After interchanging the resistances $X$ and $Y$ a new balance point is found at a distance $l_{2}$ from end $A$ . What are the values of $X$ (in $\Omega$ and $l_{2}$ ?
Question 9 image
a.
$19. 15\,\Omega$ and $39. 5\, cm$
b.
$8. 16\,\Omega$ and $60. 5\, cm$ Correct Answer
c.
$8. 16\,\Omega$ and $39. 5\, cm$
d.
$19. 15\,\Omega$ and $60. 5\, cm$

No explanation saved for this question yet.

Q10 mcq
Take the mean distance of the moon and the sun from the earth to be $0.4 \times 10^{6}\, km$ and $150 \times 10^{6}\, km$ , respectively. Their masses are $\,8 \times 10^{22} kg$ and $2 \times 10^{30} kg$ , respectively. The radius of the earth is $6400\, km$ . Let $\Delta F_{1}$ be the difference in the forces exerted by the moon at the nearest and farthest point on the earth, and $\Delta F_{2}$ be the difference in the forces exerted by the sun at the nearest and farthest points on the earth. Then, the number closest to $\frac{\Delta F_{1}}{\Delta F_{2}}$ is,
a.
$6$
b.
$10^{-2}$
c.
$2$ Correct Answer
d.
$0. 6$

No explanation saved for this question yet.

🎉 10 Free Sample Solutions Completed

Unlock All 90 Questions & Solutions

Sign up free in seconds to unlock step-by-step AI answers for the remaining 80 questions.

Q11 mcq
A Helmholtz coil has a pair of loops, each with $N$ turns and radius $R$ . They are placed coaxially at distance $R$ and the same current $I$ flows through the loops in the same direction. The magnitude of the magnetic field at $P,$ midway between the centres $A$ and $C,$ is given by [Refer to figure given below]:
Question 11 image
a.
$\frac{8N\mu _{0}I}{5^{1/2}R}$
b.
$\frac{4N\mu _{0}I}{5^{3/2}R}$
c.
$\frac{4N\mu _{0}I}{5^{1/2}R}$
d.
$\frac{8N\mu _{0}I}{5^{3/2}R}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q12 mcq
An automobile, traveling at $40\, km \,h^{-1}$ , can be stopped at a distance of $40\,m$ by applying brakes. If the same automobile is traveling at $80\, km \,h^{-1}$ , the minimum stopping distance in metres is (Assume no skidding):
a.
$150\,m$
b.
$100\,m$
c.
$75\,m$
d.
$160\,m$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q13 mcq
In a screw gauge, $5$ complete rotations of the screw cause it to move a linear distance of $0. 25\, cm$ . There are $100$ circular scale divisions. The thickness of a wire measured by this screw gauge gives a reading of $4$ main scale divisions and $30$ circular scale divisions. Assuming negligible error, the thickness of the wire is
a.
$0. 4300\, cm$
b.
$0. 3150\, cm$
c.
$0. 0430\, cm$
d.
$0. 2150\, cm$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q14 mcq
A plano-convex lens becomes an optical system of $28\, cm$ focal length when its plane surface is silvered and illuminated from left to right as shown in fig $-A$ If the same lens is instead silvered on the curved surface and illuminated from another side as in fig- $B$ , it acts as an optical system of focal length $10\, cm$ . The refractive index of the material of the lens is:
Question 14 image
a.
$1. 55$
b.
$1. 50$
c.
$1. 75$
d.
$1. 51$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q15 mcq
A uniform rod $AB$ is suspended from a point $X$ , at a variable distance $x$ from $A$ , as shown. To make the rod horizontal, a mass $m$ is suspended from its end $A$ . A set of $(m, \,x)$ value is recorded. The appropriate variables that give a straight line, when plotted, are:
Question 15 image
a.
$m,x^{2}$
b.
$m, \frac{1}{x^{2}}$
c.
$m, \frac{1}{x}$
d.
$m,x$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q16 mcq
A tuning fork vibrates with frequency $256\, Hz$ and gives one beat per second with the third normal mode of vibration of an open pipe. What is the length of the pipe? (speed of sound in air is $340\,m\,s^{-1}$ )
a.
$220\, cm$
b.
$200\, cm$
c.
$190\, cm$
d.
$180\, cm$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q17 mcq
A thin uniform tube is bent into a circle of radius r in the vertical plane. Equal volumes of two immiscible liquids, Whose densities are $\rho _{1}$ and $\rho _{2}\,(\rho _{1} >\rho _{2}\,),$ fill half the circle. The angle $\theta$ between the radius vector passing through the common interface and the vertical is:
a.
$\theta = tan^{-1} \frac{\pi}{2}(\frac{$\rho$_{1+}$\rho$_{2}}{$\rho$_{1}-$\rho$_{2}})$
b.
$\theta = tan^{-1}[(\frac{$\rho$_{1-}$\rho$_{2}}{$\rho$_{1}+$\rho$_{2}})]$
c.
$\theta = tan^{-1} \frac{\pi}{2}(\frac{$\rho$_{2}}{$\rho$_{1}})$
d.
$\theta = tan^{-1}\pi (\frac{$\rho$_{1}}{$\rho$_{2}})$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q18 mcq
In a common emitter configuration with suitable bias, it is given that $R_{L}$ is the load resistance and $R_{BE}$ is small-signal dynamic resistance (input side). Then, voltage gain, current gain and power gain are given, respectively, by: $\beta$ is current gain, $I_{B}$ , $I_{C}$ and $I_{E}$ are respectively base, collector, and emitter currents.
a.
$\beta \frac{R_{L}}{R_{BE}}, \frac{\Delta I_{C}}{\Delta I_{B}},\beta ^{2} \frac{R_{L}}{R_{BE}}$
b.
$\beta \frac{R_{L}}{R_{BE}} , \frac{\Delta I_{E}}{\Delta I_{B}},\beta ^{2} \frac{R_{L}}{R_{BE}}$
c.
$\beta ^{2} \frac{R}{R_{BE}}^{L} , \frac{\Delta I_{C}}{\Delta I_{B}},\beta \frac{R}{R_{BE}}^{L}$
d.
$\beta ^{2} \frac{R}{R_{BE}}^{L} , \frac{\Delta I_{C}}{\Delta I_{E}},\beta ^{2} \frac{R}{R_{BE}}^{L}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q19 mcq
A particle is oscillating on the $x$ -axis with an amplitude $2\, cm$ about the point $x_{0} = 10\, cm$ with a frequency. A concave mirror of focal length $5\, cm$ is placed at the origin (see figure). Identify the correct statements? (i) The image executes periodic motion. (ii) The image executes non-periodic motion. (iii) The turning points of the image are asymmetric with respect to the image of the point at $X = 10\, cm$ . (iv) The distance between the turning points of the oscillation of the image is $\frac{100}{21}\, cm$ .
Question 19 image
a.
(ii, iii)
b.
(i, iii, iv)
c.
(i, iv)
d.
(ii, iv)
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q20 mcq
A monochromatic beam of light has a frequency $v= \frac{3}{2\pi} \times 10^{12} Hz$ and is propagating along the direction $\frac{ˆi+ˆj}{\sqrt{2}}$ . It is polarized along the $ˆk$ direction. The acceptance form the magnetic field is:
a.
$ˆ$ $\frac{E_{0}}{C}(\frac{ˆi+ˆj}{\sqrt{2}})\, Cos[10^{4} \frac{(i+ˆj)}{\sqrt{2}}. \vec{r}\, - (3 \times 10^{12})t]$
b.
$ˆ$ $\frac{E_{0}}{C} ˆk\, Cos[10^{4} \frac{(i+ˆj)}{\sqrt{2}}. \vec{r}+(3 \times 10^{12})t]$
c.
$ˆ ˆ ˆ$ $\frac{E_{0}}{C} \frac{(i-j)}{\sqrt{2}}\, Cos[10^{4} \frac{(i+ˆj)}{\sqrt{2}}. \vec{r}+(3 \times 10^{12})t]$
d.
$ˆ ˆ ˆ ˆ$ $\frac{E_{0}}{C} \frac{(i+j+k)}{\sqrt{3}}Cos[10^{4} \frac{(i+ˆj)}{\sqrt{2}}. \vec{r}+(3 \times 10^{12})t]$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q21 mcq
The equivalent capacitance between $A$ and $B$ in the circuit is given below.
Question 21 image
a.
$3. 6\,$ $\mu$ $F$
b.
$2. 4\,$ $\mu$ $F$
c.
$4. 9\mu F$
d.
$5. 4\mu F$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q22 mcq
An ideal capacitor of capacitance $0 .2 \,$ $\mu$ $F$ is charged to a potential difference of $10\,V$ . The charging battery is then disconnected. The capacitor is then connected to an ideal inductor of self inductance $0. 5\, mH$ . The current at a time when the potential difference across the capacitor is $5\,V$ is:
a.
$0. 15\,A$
b.
$0. 17\,A$
c.
$0. 34\,A$
d.
$0. 25\,A$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q23 mcq
A body of mass $M$ and charge $q$ is connected to a spring of spring constant $k$ . It is oscillating along $x$ -direction about its equilibrium position in the horizontal plane, taken to be at $x= 0$ , with an amplitude $A$ . An electric field $E$ is applied along the $x$ -direction. Which of the following statements is correct?
a.
The total energy of the system is $\frac{1}{2}m\omega ^{2}A^{2}+ \frac{1}{2} \frac{q^{2}E^{2}}{k}$
b.
The new equilibrium position is at a distance $\frac{2qE}{k}$ from $x= \,0$
c.
The new equilibrium position is at a distance $\frac{qE}{2k}$ from $x= \,0$
d.
The total energy of the system is $\frac{1}{2}m\omega ^{2}A^{2}- \frac{1}{2} \frac{q^{2}E^{2}}{k}$ .
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q24 mcq
The $B- H$ curve for a ferromagnet is shown in the figure. The ferromagnet is placed inside a long solenoid with $1000\, turns \, cm^{-1}$ . The current that should be passed in the solenoid to demagnetize the ferromagnet completely is,
Question 24 image
a.
$2\, mA$
b.
$20\,$ $\mu$ $A$
c.
$1\, mA$
d.
$40\,$ $\mu$ $A$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q25 mcq
The energy required to remove the electron from a singly ionized Helium atom is $2. 2$ times the energy required to remove an electron from helium atom. The total energy required to ionize the Helium atom completely is close to
a.
$34\, eV$
b.
$20\, eV$
c.
$79\, eV$
d.
$109\, eV$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q26 mcq
The velocity time graphs of a car and a scooter are shown in the figure. (i) The difference between the distance travelled by the car and the scooter in 15 s and (ii) the time at which the car will catch up with the scooter are, respectively.
Question 26 image
a.
$112. 5\,m$ and $22. 5\,s$
b.
$337. 5\,m$ and $25\,s$
c.
$225. 5\,m$ and $10\,s$
d.
$112. 5\,m$ and $15\,s$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q27 mcq
In the given circuit all resistance is of the value of $R$ ohm each. The equivalent resistance between $A$ and $B$ is:
Question 27 image
a.
$\frac{5R}{2}$
b.
3R
c.
$\frac{5R}{3}$
d.
$2R$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q28 mcq
A solution containing active cobalt $^{60}_{27}Co$ having an activity of $0 .8 \,$ $\mu$ $Ci$ and decay constant $\lambda$ is injected in an animal's body. When $1\,cm^{3}$ blood is drawn from the animal's body after $10\,h$ of injection, the activity was found to be $300\, dpm$ (decays per minute), then the total volume of blood in the animal's body is close to $[1\,Ci = 3 .7 \times 10^{10}\, dps$ (decays per second) and at $t= 10\,h$ the value of $e^{-\lambda t} = 0.84]$
a.
$4\,L$
b.
$6\,L$
c.
$5\,L$
d.
$7\,L$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q29 mcq
A force of $40\,N$ acts on a point $B$ at the end of an L-shaped object as shown in the figure. The angle $\theta$ that will produce the maximum moment of the force about point $A$ is given by:
Question 29 image
a.
$tan\theta = 4$
b.
$tan\theta = \frac{1}{4}$
c.
$tan\theta = \frac{1}{2}$
d.
$tan\theta = 2$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q30 mcq
The number of amplitude-modulated broadcast stations that can be accommodated in a $300\, kHz$ bandwidth for the highest modulating frequency $15\, kHz$ will be:
a.
$15$
b.
$20$
c.
$8$
d.
$10$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q31 mcq
In the above compound, the bond orders of bonds $(I)$ and $(II)$ are:
a.
$(I) < 2, \,(II) > 2$
b.
$(I) > 2, \,(II) > 2$
c.
$(I) > 2, \,(II) < 2$
d.
$(I) < 2, \,(II) < 2$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q32 mcq
When an electric current is passed through acidified water, 112 mL of hydrogen gas at N.T.P was collected at the cathode in 965 seconds. The current passed, in ampere, is:
a.
2.0
b.
0.1
c.
0.5
d.
1.0
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q33 mcq
The copolymer formed by addition polymerization of styrene and acrylonitrile in the presence of peroxide is
Question 33 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q34 mcq
The increasing order of nitration in the acidic medium of the following compounds is:
Question 34 image
a.
$(a) < (b) < (d) < (c)$
b.
$(a) < (b) < (c) < (d)$
c.
$(b) < (a) < (c) < (d)$
d.
$(b) < (a) < (d) < (c)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q35 mcq
Which of the following is a Lewis acid?
a.
$PH_{3}$
b.
$NF_{3}$
c.
$NaH$
d.
$B(CH_{3})_{3}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q36 mcq
Which of the following statements about colloids is false?
a.
When silver nitrate solution is added to potassium iodide solution a negatively charged colloidal solution is formed.
b.
Freezing point of colloidal solution is lower than true solution at same concentration of a solute.
c.
Colloidal particles can pass through ordinary filter paper.
d.
When excess of electrolyte is added to colloidal solution, colloidal particle will be precipitated.
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q37 mcq
The main reduction product of the following compound with $NaBH_{4}$ in methanol is:
Question 37 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q38 mcq
The IUPAC name of the following compound is
Question 38 image
a.
$3-$ ethyl $-4-$ methylhex $-4-$ ene
b.
$4, 4-$ diethyl $-3-$ methylbut $-2-$ ene
c.
$4-$ methyl $-3-$ ethylhex $-4-$ ene
d.
$4-$ ethyl $-3-$ methylhex $-2-$ ene
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q39 mcq
In which of the following reactions, an increase in the volume of the container will favour the formation of products?
a.
$4 NH_{3}\,(g) + \,5O_{2}\,(g) \rightleftharpoons \,4 NO(g) + \,6H_{2}O(l)$
b.
$2 NO_{2}\,(g)\, \rightleftharpoons \,2 NO(g)\, + \,O_{2}(g)$
c.
$3O_{2}\,(g)\,\, \rightleftharpoons \,2O_{3}(g)$
d.
$H_{2}\,(g)\, + \,I_{2}\,(g)\, \rightleftharpoons \,2HI(g)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q40 mcq
The correct match between items of List-I and List-II is List - I List - II (A) Coloured impurity (P) Steam distillation (B) Mixture of o - nitrophenol and p -nitrophenol (Q) Fractional distillation (C) Crude Naphtha (R) Charcoal treatment (D) Mixture of glycerol and sugars (S) Distillation under reduced pressure
a.
$(A) -(R), (B) -(S), (C) -(P), (D) -(Q)$
b.
$(A) -(P), (B) -(S), (C) -(R), (D) -(Q)$
c.
$(A) -(R), (B) -(P), (C) -(Q), (D) -(S)$
d.
$(A) -(R), (B) -(P), (C) -(S), (D) -(Q)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q41 mcq
An ideal gas undergoes a cyclic process as shown in the figure $\Delta U_{BC} = -5 KJmol^{-1}, q_{AB} = 2 KJmol^{-1}$ $W_{AB} = -5 KJmol^{-1}, W_{CA} = 3 KJmol^{-1}$ Heat absorbed by the system during process $CA \,$ is
Question 41 image
a.
$-5 KJmol^{-1}$
b.
$+5 KJmol^{-1}$
c.
$-18 KJmol^{-1}$
d.
$18 KJmol^{-1}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q42 mcq
Which of the following will not exist in Zwitterionic form at $pH = 7$ ?
Question 42 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q43 mcq
For which of the following reactions, $\Delta H$ is equal to $\Delta U$ ?
a.
$N_{2}\,(g) + 3H_{2}\,(g) \rightarrow 2 NH\rightarrow_{3}\,(g)$
b.
$2 HI \,(g) \rightarrow H\rightarrow_{2}(g) + I_{2}(g)$
c.
$2 SO_{2}\,(g) + O_{2}\,(g) \rightarrow 2 SO\rightarrow_{3}\,(g)$
d.
$2 NO_{2}\,(g) \rightarrow N\rightarrow_{2}O_{4}\,(g)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q44 mcq
Which of the following is the correct structure of adenosine?
Question 44 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q45 mcq
Which of the following will most readily give the dehydrohalogenation product?
Question 45 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q46 mcq
The major product of the following reaction is:
Question 46 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q47 mcq
The reagent(s) required for the following conversion are:
Question 47 image
a.
$(i)\, NaBH_{4}\,(ii)\, Raney \, Ni /H_{2}\,(iii)\,H_{3}O^{+}$
b.
$(i)\, LiAlH_{4}\,(ii)\,\,H_{3}O^{+}$
c.
$(i)\,B_{2}H_{6}\,(ii)DIBAL -H\,\,(iii)H_{3}O^{+}$
d.
$(i)\,B_{2}H_{6}\,(ii) SnCl_{2}/ HCl \,(iii)\,H_{3}O^{+}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q48 mcq
A sample of $NaClO_{3}$ is converted by heat to $NaCl$ with a loss of $0. 16\,g$ of oxygen. The residue is dissolved in water and precipitated as $AgCl$ . The mass of $AgCl$ (in $g$ ) obtained will be: (Given: Molar mass of $AgCl = 143 .5 \,g\, mol^{-1}$ )
a.
$0. 35$
b.
$0. 54$
c.
$0. 41$
d.
$0. 48$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q49 mcq
Which of the following arrangements shows the schematic alignment of magnetic moments of antiferromagnetic substance?
Question 49 image
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q50 mcq
The minimum volume of water required to dissolve 0.1 g lead (II) chloride to get a saturated solution ( $K_{sp}$ of $PbCl_{2} = 3.2 \times 10^{-8}$ ;atomic mass of $Pb= 207\,u$ ) is:
a.
1.798 L
b.
0.36 L
c.
17.98 L
d.
0.18 L
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q51 mcq
The decreasing order of bond angles in $\, BF_{3}, \, NH_{3}, \, PF_{3}$ and $I^{-}_{3}$ is:
a.
$I^{-}_{3} > \, BF_{3} > \, NH_{3} > \, PF_{3}$
b.
$BF_{3} > \,I^{-}_{3} > \, PF_{3} > \, NH_{3}$
c.
$BF_{3} > \, NH_{3} > \, PF_{3} > I^{-}_{3}$
d.
$I^{-}_{3} > \, NH_{3} > \, PF_{3} > \, BF_{3}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q52 mcq
$N_{2}O_{5}$ decomposes to $NO_{2}$ and $O_{2}$ follows the first order kinetics. After $50$ minutes, the pressure inside the vessel increases from $50\, mm \, Hg$ to $87. 5\, mm \, Hg$ . The pressure of the gaseous mixture after $100$ minutes at constant temperature will be:
a.
$136. 5\, mm \, Hg$
b.
$106. 25\, mm \, Hg$
c.
$175. 0\, mm \, Hg$
d.
$116. 25\, mm \, Hg$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q53 mcq
The correct combination is
a.
$[NiCl_{4}]^{2-}-$ Square planar; $[Ni (CN)_{4}]^{2-}-$ paramagnetic
b.
$[Ni (CN)_{4}]^{2-}-$ tetrahedral; $[Ni (CO)_{4}]^{2-}-$ paramagnetic
c.
$[NiCl_{4}]^{2-}-$ paramagnetic; $[Ni (CO)_{4}]-$ tetrahedral
d.
$[NiCl_{4}]^{2-}-$ diamagnetic; $[Ni (CO)_{4}]-$ square- planar
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q54 mcq
In graphite and diamond, the percentage of p-characters of the hybrid orbitals in hybridization respectively, are
a.
$33\, and \,25$
b.
$67\, and \,75$
c.
$50\, and \,75$
d.
$33\, and \,75$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q55 mcq
Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying $0. 5\,V$ , when the radiation of $250\, nm$ is used. The work function of the metal is
a.
$4\, eV$
b.
$5. 5\, eV$
c.
$4. 5\, eV$
d.
$5\, eV$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q56 mcq
A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the before mentioned solution, a white precipitate is obtained which does not dissolve in dilute nitric acid. The anion is:
a.
$CO^{2-}_{3}$
b.
$SO^{2-}_{4}$
c.
$S^{2-}$
d.
$Cl^{-}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q57 mcq
For $Na^{+}, \, Mg^{2+}, \,F^{-}$ and $O^{2-}$ , the correct order of increasing ionic radii is:
a.
$O^{2-} < F^{-} < Na^{+} < Mg^{2+}$
b.
$Na^{+} < Mg^{2+} < F^{-} < O^{2-}$
c.
$Mg^{2+} < Na^{+} < F^{-} < O^{2-}$
d.
$Mg^{2+} < O^{2-} < \, Na^{+} < F^{-}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q58 mcq
Xenon hexafluoride on partial hydrolysis produces compounds 'X' and 'Y' and the respective oxidation states of Xe are:
a.
$XeOF_{2}\,(+4)\, and \, XeO_{3}\,(+6)$
b.
$XeOF_{4}\,(+6)\, and \, XeO_{3}\,(+6)$
c.
$XeO_{2}F_{2}\,(+6)\, and \, XeO_{2}\,(+4)$
d.
$XeOF_{4}\,(+6)\, and \, XeO_{2}F_{2}\,(+6)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q59 mcq
Identify the pair in which the geometry of the species is T-shaped and square-pyramidal, respectively,
a.
$ICl^{-}_{2}$ and $ICl_{5}.$
b.
$IO^{-}_{3}$ and $\, IO_{2}F^{-}_{2} .$
c.
$ClF_{3}$ and $IO^{-}_{4} .$
d.
$XeOF_{2}$ and $XeOF_{4}.$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q60 mcq
In the molecular orbital diagram for the molecular ion $N^{+}_{2}$ , the number of electrons in the $\sigma$ $_{2p}$ molecular orbital is
a.
$0$
b.
$2$
c.
$3$
d.
$1$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q61 mcq
If $(p\wedge ~q) \wedge (p\wedge r) \rightarrow ~\rightarrow p\vee q$ is false, then the truth values of $p, \,q$ and $r$ are respectively
a.
$T, \,T, \,T$
b.
$F, \,T, \,F$
c.
$T, \,F, \,T$
d.
$F, \,F, \,F$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q62 mcq
An aeroplane flying at a constant speed, parallel to the horizontal ground, $\sqrt{3}\, km$ above it is observed at an elevation of $60^{^{\circ}}$ from a point on the ground. If after five seconds, its elevation from the same point is $30^{^{\circ}}$ , then the speed (in $km / hr$ ) of the aeroplane is
a.
$720$
b.
$1500$
c.
$750$
d.
$1440$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q63 mcq
$||$ A box $A$ contains $2$ white, $3$ red and $2$ black balls. Another box $B$ contains $4$ white, $2$ red and $3$ black balls. If two balls are drawn at random, without replacement from a randomly, selected box and one ball turns out to be white while the other ball turns out to be red, then the probability that both balls are drawn from box $B$ is :
a.
$\frac{7}{8\,}$
b.
$\frac{9}{16\,}$
c.
$\frac{7}{16\,}$
d.
$\frac{9}{32\,}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q64 mcq
A variable plane passes through a fixed point $(3, \,2, \,1)$ and meets $x, \,y$ and $z$ -axes at $A, \,B\,&\,C$ respectively. A plane is drawn parallel to the $yz-$ plane through $A$ , a second plane is drawn parallel to the $zx-$ plane through $B$ and a third plane is drawn parallel to the $xy$ - plane through $C$ . Then the locus of the point of intersection of these three planes, is
a.
$\frac{3}{x} + \frac{2}{y} + \frac{1}{z} = 1$
b.
$\frac{1}{x} + \frac{1}{y} + \frac{1}{z} = \, \frac{11}{6}$
c.
$x+y+z= 6$
d.
$\frac{x}{3} + \frac{y}{2} + \frac{z}{1} = \,1$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q65 mcq
The area (in sq. units) of the region ${x\in R: \,x\geq 0 ,\,y\geq 0 ,\,y\geq x-2$ and $y\leq \sqrt{x}}$ is
a.
$\frac{13}{3}$
b.
$\frac{8}{3}$
c.
$\frac{10}{3}$
d.
$\frac{5}{3}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q66 mcq
If $tanA$ and $tanB$ are the roots of the quadratic equation $3x^{2} -10x-25 = 0$ , then the value of $3 sin^{2}(A+B) -10 sin(A+B) cos(A+B) -25 cos^{2}(A+B)$ is :
a.
$-25$
b.
$10$
c.
$-10$
d.
$25$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q67 mcq
$\rightarrow \rightarrow$ If $\vec{a}, \,\vec{b}, \,\vec{c}$ are unit vectors such that $\vec{a}+ 2\vec{b}+ 2\vec{c}= 0$ , then $\vec{a}\times \vec{c}$ is equal to :
a.
$\frac{1}{4}$
b.
$\frac{15}{16}$
c.
$\frac{\sqrt{15}}{4}$
d.
$\frac{\sqrt{15}}{16}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q68 mcq
If $x^{2} +y^{2} + siny= 4$ , then the value of $\frac{d^{2}y}{dx^{2}}$ at the point $(-2, \,0)$ is :
a.
$-34$
b.
$4$
c.
$-2$
d.
$-32$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q69 mcq
An angle between the plane $x+y+z= 5$ and the line of intersection of the planes, $3x+ 4y+z-1 = 0$ and $5x+ 8y+ 2z+ 14 = 0$ is
a.
$cos^{-1}(\sqrt{\frac{3}{17}})$
b.
$cos^{-1}(\frac{3}{\sqrt{17}})$
c.
$sin^{-1}(\frac{3}{\sqrt{17}} )$
d.
$sin^{-1}(\sqrt{\frac{3}{17}})$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q70 mcq
Let $S$ be the set of all real values of $k$ for which the system of linear equations $x+y+z= 2$ $2x+y- z= 3$ $3x+ 2y+kz= 4$ has a unique solution. Then, $S$ is :
a.
equal to $R\,-{0}$
b.
an empty set
c.
equal to $R$
d.
equal to ${0}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q71 mcq
Consider the following two binary relations on the set $A= {a, \,b, \,c}\, : \,R_{1} = {(c, \,a), \,(b, \,b), \,(a, \,c), \,(c, \,c), \,(b, \,c), \,(a, \,a)}$ and $R_{2} = {(a, \,b), \,(b, \,a), \,(c, \,c), \,(c, \,a), \,(a, \,a), \,(b, \,b), \,(a, \,c)}$ , then :
a.
$R_{2}$ is symmetric but it is not transitive
b.
both $R_{1}$ and $R_{2}$ are not symmetric
c.
both $R_{1}$ and $R_{2}$ are transitive
d.
$R_{1}$ is not symmetric but it is transitive
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q72 mcq
$\frac{\pi}{2}$ The value of the integral $\int sin^{4} x(1 + ln(\frac{2+sinx}{2-sinx}))dx$ is $-\frac{\pi}{2}$
a.
$\frac{3}{4}$
b.
$\frac{3}{8}\pi$
c.
$0$
d.
$\frac{3}{16} \pi$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q73 mcq
If the tangent drawn to the hyperbola $4y^{2} =x^{2} + 1$ intersect the co-ordinates axes at the distinct points $A$ and $B$ , then the locus of the midpoint of $AB$ is :
a.
$x^{2} -4y^{2} + 16x^{2}y^{2} = 0$
b.
$4x^{2} - y^{2} + 16x^{2}y^{2} = 0$
c.
$x^{2} -4y^{2} -16x^{2}y^{2} = 0$
d.
$4x^{2} - y^{2} -16x^{2}y^{2} = 0$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q74 mcq
If $n$ is the degree of the polynomial, $[\frac{2}{\sqrt{5x^{3}+1}-\sqrt{5x^{3}-1}} ]^{8} + \,[\frac{2}{\sqrt{5x^{3}+1}+\sqrt{5x^{3}-1}} ]^{8}$ and $m$ is the coefficient of $x^{n}$ in it, then the ordered pair $(n, \,m)$ is equal to
a.
$(8, \,5(10)^{4})$
b.
$(12, \,8(10)^{4})$
c.
$(12, \,(20)^{4})$
d.
$(24, \,(10)^{8})$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q75 mcq
If a right circular cone, having maximum volume, is inscribed in a sphere of radius $3\,cm$ , then the curved surface area (in $cm^{2}$ ) of this cone is :
a.
$8\sqrt{2}\pi$
b.
$6\sqrt{2}\pi$
c.
$8\sqrt{3}\pi$
d.
$6\sqrt{3}\pi$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q76 mcq
Two parabolas with a common vertex and with axes along the $x$ -axis and $y$ -axis respectively, intersect each other in the first quadrant. If the length of the latus rectum of each parabola is $3$ , then the equation of the common tangent to the two parabolas is :
a.
$\,3(x+y) + 4 = 0$
b.
$8(2x+y) + 3 = 0$
c.
$x+ 2y+ 3 = 0$
d.
$4(x+y) + 3 = 0$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q77 mcq
$n$ -digit numbers are formed using only three digits $2, \,5$ and $7$ . The smallest value of $n$ for which $900$ such distinct numbers can be formed is :
a.
$9$
b.
$7$
c.
$8$
d.
$6$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q78 mcq
If $\lambda \in R$ is such that the sum of the cubes of the roots of the equation $x^{2} + (2 - \lambda )x+ (10 - \lambda ) = 0$ is minimum, then the magnitude of the difference of the roots of this equation is :
a.
$4\sqrt{2}$
b.
$20$
c.
$2\sqrt{5}$
d.
$2\sqrt{7}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q79 mcq
In a triangle $ABC$ , coordinates of $A$ are $(1, \,2)$ and the equations of the medians through $B$ and $C$ are respectively, $x+y= 5$ and $x= 4$ . Then area of $\Delta ABC$ (in sq. units) is :
a.
$12$
b.
$4$
c.
$9$
d.
$5$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q80 mcq
If $x_{1}, \,x_{2}, \, … . . , \,x_{n}$ and $\frac{1}{h_{1}}, \,\frac{1}{h_{2}} , \, … . . , \,\frac{1}{h_{n}}$ are two A.P.s such that $x_{3} =h_{2} = 8\,&\,x_{8} =h_{7} = 20$ , then $x_{5}\cdot h_{10}$ is equal to
a.
$3200$
b.
$1600$
c.
$2650$
d.
$2560$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q81 mcq
If $b$ is the first term of an infinite geometric progression whose sum is five, then $b$ lies in the interval
a.
$[10, \, \infty )$
b.
$(-\infty , -10]$
c.
$(-10, \,0)$
d.
$(0, \,10)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q82 mcq
The mean of a set of $30$ observation is $75$ . If each observations is multiplied by non-zero number $\lambda$ and then each of them is decreased by $25$ , their mean remains the same. Then, $\lambda$ is equal to :
a.
$\frac{4}{3}$
b.
$\frac{1}{3}$
c.
$\frac{10}{3}$
d.
$\frac{2}{3}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q83 mcq
Let $S ={(\lambda , \,\mu ) \in R\times R\, : \,f(t) =(|\lambda \,|e^{|t|} - \mu )sin(2|t|), \,t\in R$ is a differential function}. Then, $S$ is a subset of :
a.
$(-\infty ,\, 0) \times R$
b.
$R\times [0 ,\, \infty )$
c.
$[0 ,\, \infty ) \times R$
d.
$R \times (-\infty ,\, 0)$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q84 mcq
If $\beta$ is one of the angles between the normals to the ellipse $x^{2} + 3y^{2} = 9$ at the points $(3 cos\theta , sin\sqrt{3} \theta )$ and $(-3 sin\theta , \sqrt{3}cos\theta ); \,\theta \in (0, \frac{\pi}{2})$ ; then $\frac{2 cot\beta}{sin 2\theta}$ is equal to :
a.
$\frac{1}{\sqrt{3}}$
b.
$\frac{\sqrt{3}}{4}$
c.
$\frac{2}{\sqrt{3}}$
d.
$\sqrt{2}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q85 mcq
The set of all $\alpha \in R$ , for which $w= \frac{1+(1-8\alpha )z}{1-z}$ is a purely imaginary number, for all $z\in C$ satisfying $|z| = 1$ and $Re(z) \neq 1$ , is :
a.
${0}$
b.
${0, \frac{1}{4}, -\frac{1}{4}}$
c.
equal to $R$
d.
an empty set
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q86 mcq
$cosx x 1$ If $f(x) = 2 sinx x^{2} 2x$ , then $_{x}lim_{\rightarrow 0\rightarrow } \frac{f^{'}(x)}{x}$ $tanx x 1$
a.
does not exist
b.
exists and is equal to $-2$
c.
exists and is equal to $0$
d.
exists and is equal to $2$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q87 mcq
$1 2$ Let $A$ be a matrix such that $A\cdot [ ]$ is a scalar matrix and $|3A| = 108$ . Then, $A^{2}$ equals : $0 3$
a.
$4 0$ $[ ]$ $-32 36$
b.
$36 -32$ $[ ]$ $0 4$
c.
$36 0$ $[ ]$ $-32 4$
d.
$4 -32$ $[ ]$ $0 36$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q88 mcq
If $f( \frac{x-4}{x+2})= 2x+ 1, \,(x\in R-{1, -2})$ , then $\int f(x)dx$ is equal to
a.
$12 ln|1 - x| -3x+C$
b.
$-12 ln|1 - x| -3x+C$
c.
$12 ln|1 - x| + 3x+C$
d.
$-12 ln|1 - x| + 3x+C$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q89 mcq
$| |$ $1, x\in [0, \,1]$ Let $y=y(x)$ be the solution of the differential equation $\frac{dy}{dx} + 2y=f(x)$ , where $f(x) = \,{$ . If $0, otherwise$ $y(0) = 0$ , then $y (\frac{3}{2})$ is
a.
$\frac{e^{2}-1}{e^{3}}$
b.
$\frac{1}{2e}$
c.
$\frac{e^{2}+1}{2e^{4}}$
d.
$\frac{e^{2}-1}{2e^{3}}$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.

Q90 mcq
A circle passes through the points $(2, 3)$ and $(4, 5)$ . If its centre lies on the line $y-4x+ 3 = 0$ , then its radius is equal to :
a.
$\sqrt{5}$
b.
$\sqrt{2}$
c.
$2$
d.
$1$
Correct Answer & Step-by-Step Solution Locked

Sign in free to reveal the correct answer and AI explanation for this question.