← JEE MAINS
JEE · combined subjects

JEE Main 2009

2009 · 90 questions · First 10 Solutions Free
Questions 1–10 have full step-by-step solutions visible. Sign in to unlock all 90 →
Q1 mcq
A transparent solid cylindrical rod has a refractive index of $\frac{2}{\sqrt{3}}$ . It is surrounded by air. A light ray is incident at the mid point of one end of the rod as shown in the figure. The incident angle $\theta$ for which the light ray grazes along the wall of the rod is
Question 1 image
a.
$sin^{-1} (\frac{1}{2})$
b.
$sin^{-1} (\frac{\sqrt{3}}{2})$
c.
$sin^{-1} (\frac{2}{\sqrt{3}})$
d.
$sin^{-1} (\frac{1}{\sqrt{3}})$ Correct Answer

No explanation saved for this question yet.

Q2 mcq
The logic circuit shown below has the input waveforms 'A' and 'B' as shown. Pick out the correct output waveform.
Question 2 image

No explanation saved for this question yet.

Q3 mcq
A mixture of light, consisting of wavelength $590\,nm$ and an unknown wavelength, illuminates Young's double slit and gives rise to two overlapping interference patterns on the screen. The central maximum of both lights coincide. Further, it is observed that the third bright fringe of known light coincides with the $4^{th\,}$ bright fringe of the unknown light. From this data, the wavelength of the unknown light is
a.
$393.4\,nm$
b.
$885.0\,nm$
c.
$442.5\,nm$ Correct Answer
d.
$776.8\,nm$

No explanation saved for this question yet.

Q4 mcq
A motor cycle starts from rest and accelerates along a straight path at $2\,m/s^{2}$ . At the starting point of the motor cycle there is a stationary electric sire. How far has the motor cycle gone when the driver hears the frequency of the siren at $94%$ of its value when the motor cycle was at rest? (speed of sound $= 330\,ms^{-1})$
a.
$49\,m$
b.
$98\,m$ Correct Answer
c.
$147\,m$
d.
$196\,m$

No explanation saved for this question yet.

Q5 mcq
The magnitude of the magnetic field $(B)$ due to loop $ABCD$ at the origin $(O)$ is
a.
zero
b.
$\frac{\mu _{0}(b-a)}{24ab}$ Correct Answer
c.
$\frac{\mu _{0}I}{4\pi}[ \frac{b-a}{ab}]$
d.
$\frac{\mu _{o}|}{4\pi} [2(b- a) + \frac{\pi}{3}(a+b)]$

No explanation saved for this question yet.

Q6 mcq
Two points $P$ and $Q$ are maintained at the potentials of $10\,V$ and $-4\,V$ respectively. The work done in moving 100 electrons from $P$ to $Q$ is
a.
$-19 \times 10^{-17}\,J$
b.
$9.60 \times 10^{-17}\,J$
c.
$-2.24 \times 10^{-16}\,J$
d.
$2.24 \times 10^{-16}\,J$ Correct Answer

No explanation saved for this question yet.

Q7 mcq
This question contains Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement-1: The temperature dependence of resistance is usually given as $R=R_{0}(1 +\alpha \Delta t)$ . The resistance of a wire changes from $100\Omega$ to $150\Omega$ when its temperature is increased from $27^{\circ }C$ to $227^{\circ }C$ . This implies that $\alpha = 2.5 \times 10^{-3}/^{\circ }C$ . Statement 2: $R=R_{i}(1 +\alpha \Delta T)$ is valid only when the change in the temperature $\Delta T$ is small and $\Delta R= (R- R_{0}) \ll R_{0}$ .
a.
Statement-1 is true, Statement-2 is false Correct Answer
b.
Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1.
c.
Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation of Statement-1.
d.
Statement-1 is false, Statement-2 is true

No explanation saved for this question yet.

Q8 mcq
A charge $Q$ is placed at each of the opposite corners of a square. A charge $q$ is placed at each of the other two corners. If the net electrical force on $Q$ is zero, then the $Q/q$ equals
a.
$-2\sqrt{2}$ Correct Answer
b.
$-1$
c.
1
d.
$-\frac{1}{\sqrt{2}}$

No explanation saved for this question yet.

Q9 mcq
Three sound waves of equal amplitudes have frequencies $(v-1),v, (v+ 1)$ . They superpose to give beats. The number of beats produced per second will be
a.
4
b.
3
c.
2 Correct Answer
d.
1

No explanation saved for this question yet.

Q10 mcq
The transition from the state $n= 4$ to $n= 3$ in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from
a.
$2 \rightarrow 1\rightarrow$
b.
$3 \rightarrow 2\rightarrow$
c.
$4 \rightarrow 2\rightarrow$
d.
$5 4$ Correct Answer

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 particle has an initial velocity $3\hat{i}+ 4\hat{j}$ and an acceleration of $0.4\hat{i}+ 0.3\hat{j}$ . Its speed after 10 s is
a.
10 units
b.
$7\sqrt{2}$ units
c.
7 units
d.
$8.5$ units
Correct Answer & Step-by-Step Solution Locked

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

Q12 mcq
One kg of a diatomic gas is at a pressure of $8 \times 10^{4}\,N/m^{2}$ . The density of the gas is $4\,kg/m^{-3}$ . What is the energy of the gas due to its thermal motion?
a.
$3 \times 10^{4}\,J$
b.
$5 \times 10^{4}\,J$
c.
$6 \times 10^{4}\,J$
d.
$7 \times 10^{4}\,J$
Correct Answer & Step-by-Step Solution Locked

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

Q13 mcq
Let $P(r) = \frac{Q}{\pi R^{4}}r$ be the charge density distribution for a solid sphere of radius $R$ and total charge $Q$ . for a point ' $p$ ' inside the sphere at distance $r_{1}$ from the centre of the sphere, the magnitude of electric field is
a.
0
b.
$\frac{Q}{4\pi \epsilon _{0}r^{2}_{1}}$
c.
$\frac{Qr^{2}}{4\pi \epsilon _{0}R^{4}}^{1}$
d.
$\frac{Q^{2}}{3\pi \epsilon _{0}R^{4}}^{1}$
Correct Answer & Step-by-Step Solution Locked

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

Q14 mcq
A thin uniform rod of length $\ell$ and mass $m$ is swinging freely about a horizontal axis passing through its end. Its maximum angular speed is $\omega$ . Its centre of mass rises to a maximum height of
a.
$\frac{1}{3} \frac{\ell ^{2}\omega ^{2}}{g}$
b.
$\frac{1}{6} \frac{\ell \omega}{g}$
c.
$\frac{1}{2} \frac{\ell ^{2}\omega ^{2}}{g}$
d.
$\frac{1}{6} \frac{\ell ^{2}\omega ^{2}}{\,g}$
Correct Answer & Step-by-Step Solution Locked

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

Q15 mcq
The above is a plot of binding energy per nucleon $E_{b}$ , against the nuclear mass $M;A,B,C,D,E,F$ correspond to different nuclei. Consider four reactions: (i) $\vec{A}+B\rightarrow \rightarrow C+\epsilon$ (ii) $C \rightarrow A + B +\rightarrow \epsilon$ (iii) $D + E \rightarrow F +\rightarrow \epsilon$ and (iv) $F \rightarrow \rightarrow D+E+\epsilon$ where $\epsilon$ is the energy released? In which reactions is $\epsilon$ positive?
Question 15 image
a.
(i) and (iv)
b.
(i) and (iii)
c.
(ii) and (iv)
d.
(ii) and (iii)
Correct Answer & Step-by-Step Solution Locked

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

Q16 mcq
Assuming the gas to be ideal the work done on the gas in taking it from $A$ to $B$ is
a.
$200R$
b.
$300R$
c.
$400R$
d.
$500R$
Correct Answer & Step-by-Step Solution Locked

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

Q17 mcq
The work done on the gas in taking it from $D$ to $A$ is
a.
$-414R$
b.
$+414R$
c.
$-690R$
d.
$+690R$
Correct Answer & Step-by-Step Solution Locked

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

Q18 mcq
Two wires are made of the same material and have the same volume. However wire 1 has crosssectional area $A$ and wire-2 has cross-sectional area $3A$ . If the length of wire 1 increases by $\Delta x$ on applying force $F$ , how much force is needed to stretch wire 2 by the same amount?
a.
$F$
b.
$4\,F$
c.
$6\,F$
d.
$9\,F$
Correct Answer & Step-by-Step Solution Locked

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

Q19 mcq
The height at which the acceleration due to gravity becomes $\frac{g}{9}$ (where $g =$ the acceleration due to gravity on the surface of the earth) in terms of $R$ , the radius of the earth is
a.
$2R$
b.
$\frac{R}{\sqrt{2}}$
c.
$\frac{R}{2}$
d.
$\sqrt{2}R$
Correct Answer & Step-by-Step Solution Locked

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

Q20 mcq
In an experiment the angles are required to be measured using an instrument. 29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale. If the smallest division of the main scale is half-a- degree $(= 0.5^{\circ })$ , then the least count of the instrument is
a.
one minute
b.
half minute
c.
one degree
d.
half degree
Correct Answer & Step-by-Step Solution Locked

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

Q21 mcq
A p-n junction (D) shown in the figure can act as a rectifier. An alternating current source $(V)$ is connected in the circuit.
Question 21 image
Correct Answer & Step-by-Step Solution Locked

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

Q22 mcq
If $x,v$ and a denote the displacement, the velocity and the acceleration of a particle executing simple harmonic motion of time period $T$ , then, which of the following does not change with time?
a.
$a^{2}T^{2} + 4\pi ^{2}v^{2}$
b.
$\frac{aT}{x}$
c.
$aT + 2\pi v$
d.
$\frac{aT}{v}$
Correct Answer & Step-by-Step Solution Locked

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

Q23 mcq
Consider a rubber ball freely falling from a height $h= 4.9\,m$ onto a horizontal elastic plate. Assume that the duration of collision is negligible and the collision with the plate is totally elastic. Then the velocity as a function of time the height as function of time will be
Question 23 image
Correct Answer & Step-by-Step Solution Locked

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

Q24 mcq
This question contains Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement - 1: For a charged particle moving from point $P$ to point $Q$ , the net work done by an electrostatic field on the particle is independent of the path connecting point $P$ to point $Q$ . Statement-2: The net work done by a conservative force on an object moving along a closed loop is zero
a.
Statement-1 is true, Statement-2 is false
b.
Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1.
c.
Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation of Statement-1.
d.
Statement-1 is false, Statement-2 is true
Correct Answer & Step-by-Step Solution Locked

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

Q25 mcq
A long metallic bar is carrying heat from one of its ends to the other end under steady-state. The variation of temperature $\theta$ along the length $x$ of the bar from its hot end is best described by which of the following figure.
Question 25 image
Correct Answer & Step-by-Step Solution Locked

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

Q26 mcq
Due to the presence of the current $l_{1}$ at the origin
a.
The forces on $AB$ and $DC$ are zero
b.
The forces on $AD$ and $BC$ are zero
c.
The magnitude of the net force on the loop is given by $\frac{\mu _{0}I_{1}}{4\pi}[2(b- a) + \frac{\pi}{3}(a+b)]$
d.
The magnitude of the net force on the loop is given by $\frac{\mu _{0}\parallel _{1}}{24ab}(b- a)$
Correct Answer & Step-by-Step Solution Locked

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

Q27 mcq
In an optics experiment, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance $u$ and the image distance $v$ , from the lens, is plotted using the same scale for the two axes. A straight line passing through the origin and making an angle of $45^{\circ }$ with the x-axis meets the experimental curve at $P$ . The coordinates of $P$ will be
a.
$(2f, 2f)$
b.
$(\frac{f}{2}, \frac{f}{2})$
c.
$(f,f)$
d.
$(4f, 4f)$
Correct Answer & Step-by-Step Solution Locked

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

Q28 mcq
The surface of a metal is illuminated with the light of $400\,nm$ . The kinetic energy of the ejected photoelectrons was found to be $1.68eV$ . The work function of the metal is $(hc = 1240eVnm)$
a.
$3.09eV$
b.
$1.41eV$
c.
$151eV$
d.
$1.68eV$
Correct Answer & Step-by-Step Solution Locked

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

Q29 mcq
An inductor of inductance $L = 400mH$ and resistors of resistances $R_{1} = 2\Omega$ and $R_{2} = 2\Omega$ are connected to a battery of emf $12\,V$ as shown in the figure. The internal resistance of the battery is negligible. The switch $S$ is closed at $t= 0$ . The potential drop across $L$ as a function of time is
Question 29 image
a.
$6e^{-5t}V$
b.
$\frac{12}{t}e^{-3t}V$
c.
$6(1 - e^{-t/0.2})V$
d.
$12e^{-5t}V$
Correct Answer & Step-by-Step Solution Locked

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

Q30 mcq
The net work done on the gas in the cycle ABCDA is
a.
Zero
b.
$276R$
c.
$1076R$
d.
$1904R$
Correct Answer & Step-by-Step Solution Locked

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

Q31 mcq
Copper crystallizes in fcc with a unit cell length of $361pm$ . What is the radius of copper atom ?
a.
$108pm$
b.
$127pm$
c.
157 pm
d.
$181pm$
Correct Answer & Step-by-Step Solution Locked

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

Q32 mcq
Given : $E^{\circ }_{Fe^{3+}/Fe} = -0.036\,V, E^{\circ }_{Fe^{2+}/Fe} = -0.439\,V$ . The value of standard electrode potential for the change, $Fe^{3+}_{(aq\,)} + e^{-} \rightarrow Fe\rightarrow^{2+}(aq)$ will be :
a.
$-0.072\,V$
b.
$0.385\,V$
c.
$0.770\,V$
d.
$-0.270$
Correct Answer & Step-by-Step Solution Locked

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

Q33 mcq
The IUPAC name of neopentane is
a.
2-methylbutane
b.
2, 2-dimethylpropane
c.
2-methylpropane
d.
2,2-dimethylbutane
Correct Answer & Step-by-Step Solution Locked

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

Q34 mcq
In a fuel cell methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is $CH_{3}OH(\ell ) + \frac{3}{2}O_{2}(\,g) \rightarrow CO\rightarrow_{2}(\,g) + 2H_{2}O(\ell )$ At $298\,K$ standard Gibb's energies of formation for $CH_{3}OH(\ell ), H_{2}O(\ell )$ and $CO_{2}(\,g)$ are $-166.2, -237.2$ and $-394.4\,kJ\,mol^{-1}$ respectively. If standard enthalpy of combustion of methanol is $-726\,kJ\,mol^{-1}$ , efficiency of the fuel cell will be
a.
$80%$
b.
$87%$
c.
$90%$
d.
$97%$
Correct Answer & Step-by-Step Solution Locked

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

Q35 mcq
Using MO theory predict which of the following species has the shortest bond length ?
a.
$O^{2+}_{2}$
b.
$O^{+}_{2}$
c.
$O^{-}_{2}$
d.
$O^{2-}_{2}$
Correct Answer & Step-by-Step Solution Locked

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

Q36 mcq
Knowing that the Chemistry of lanthanoids $(Ln)$ is dominated by its $+3$ oxidation state, which of the following statements in incorrect?
a.
Because of the large size of the Ln (III) ions the bonding in its compounds is predominantly ionic in character.
b.
The ionic sizes of Ln (III) decrease in general with increasing atomic number.
c.
Ln (III) compounds are generally colourless.
d.
Ln (III) hydroxides are mainly basic in character.
Correct Answer & Step-by-Step Solution Locked

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

Q37 mcq
The alkene that exhibits geometrical isomerism is:
a.
propene
b.
2-methyl propene
c.
2-butene
d.
2- methyl -2- butene
Correct Answer & Step-by-Step Solution Locked

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

Q38 mcq
Which of the following on heating with aqueous $KOH$ , produces acetaldehyde ?
a.
$CH_{3}COCl$
b.
$CH_{3}CH_{2}Cl$
c.
$CH_{2}ClCH_{2}Cl$
d.
$CH_{3}CHCl_{2}$
Correct Answer & Step-by-Step Solution Locked

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

Q39 mcq
In context with the transition elements, which of the following statements is incorrect?
a.
In addition to the normal oxidation states, the zero oxidation state is also shown by these elements in complexes.
b.
In the highest oxidation states, the transition metal show basic character and form cationic complexes.
c.
In the highest oxidation states of the first five transition elements (Sc to Mn), all the $4s$ and $3d$ electrons are used for bonding.
d.
Once the $d^{5}$ configuration is exceeded, the tendency to involve all the 3d electrons in bonding decreases.
Correct Answer & Step-by-Step Solution Locked

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

Q40 mcq
In Cannizzaro reaction qiven below
Question 40 image
a.
the attack of : $OH$ at the carboxyl group
b.
the transfer of hydride to the carbonyl group
c.
the abstraction of proton from the carboxylic group
d.
the deprotonation of $PhCH_{2}OH$
Correct Answer & Step-by-Step Solution Locked

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

Q41 mcq
A liquid was mixed with ethanol and a drop of concentrated $H_{2}SO_{4}$ was added. A compound with a fruity smell was formed. The liquid was:
a.
$CH_{3}OH$
b.
$HCHO$
c.
$CH_{3}COCH_{3}$
d.
$CH_{3}COOH$
Correct Answer & Step-by-Step Solution Locked

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

Q42 mcq
Buna-N synthetic rubber is a copolymer of :
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
The major product obtained on interaction of phenol with sodium hydroxide and carbon dioxide is :
a.
benzoic acid
b.
salicylaldehyde
c.
salicylic acid
d.
phthalic acid
Correct Answer & Step-by-Step Solution Locked

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

Q44 mcq
Solid Ba $(NO_{3})_{2}$ is gradually dissolved in a $1.0 \times 10^{-4}MNa_{2}CO_{3}$ solution. At what concentration of $Ba^{2+}$ will a precipitate begin to form ? $(K_{sp}$ for $BaCO_{3} = 5.1 \times 10^{-9})$ .
a.
$4.1 \times 10^{-5}M$
b.
$5.1 \times 10^{-5}M$
c.
$8.1 \times 10^{-8}M$
d.
$8.1 \times 10^{-7}M$
Correct Answer & Step-by-Step Solution Locked

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

Q45 mcq
$---$ Arrange the carbanions, $(CH_{3})_{3}C, CCl_{3}, (CH_{3})_{2}CH, C_{6}H_{5}CH_{2}$ , in order of their decreasing stability : $--------$
a.
$C_{8}H_{5}CH_{2} > CCl_{3} > (CH_{3})_{3}C > (CH_{3})_{2}CH$
b.
$(CH_{3})_{2}CH > CCl_{3} > C_{6}H_{5}CH_{2} > (CH_{3})_{3}C$ $--------$
c.
$CCl_{3} > C_{8}H_{5}CH_{2} > (CH_{3})_{2}CH > (CH_{3})_{3}C$
d.
$(CH_{3})_{3}C > (CH_{3})_{2}CH > C_{6}H_{5}CH_{2} > CCl_{3}$
Correct Answer & Step-by-Step Solution Locked

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

Q46 mcq
Which one of the following reactions of Xenon compounds is not feasible ?
a.
$XeO_{3}+ 6HF Xe_{6}+ 3H_{2}O$
b.
$3Xe_{4}+ 6H_{2}O \rightarrow 2Xe + XeO\rightarrow_{3}+ 12HF + 1.5O_{2}$
c.
$2XeF_{2}+ 2H_{2}\vec{O}\rightarrow 2Xe + 4HF + O\rightarrow_{2}$
d.
$XeF_{6}+ RbF \rightarrow Rb (XeF\rightarrow_{7}]$
Correct Answer & Step-by-Step Solution Locked

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

Q47 mcq
In an atom, an electron is moving with a speed of $600\,m/s$ with an accuracy of $0.005%$ . Certainity with which the position of the electron can be located is $(h= 6.6 \times 10^{-34}\,kg\,m^{2}\,s^{-1}$ , mass of electron, $e_{m} = 9.1 \times 10^{-31}\,kg$ )
a.
$1.52 \times 10^{-4}\,m$
b.
$5.10 \times 10^{-3}\,m$
c.
$1.92 \times 10^{-3}\,m$
d.
$3.84 \times 10^{-3}\,m$
Correct Answer & Step-by-Step Solution Locked

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

Q48 mcq
Calculate the wavelength (in nanometer) associated with a proton moving at $1.0 \times 10^{3}\,ms^{-1}$ (Mass of proton $= 1.67 \times 10^{-27}\,kg$ and $h = 6.63 \times 10^{-34}Js$ ):
a.
$0.032\,nm$
b.
$0.40\,nm$
c.
$2.5\,nm$
d.
$14.0\,nm$
Correct Answer & Step-by-Step Solution Locked

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

Q49 mcq
In which of the following arrangements, the sequence is not strictly according to the property written against it ?
a.
$CO_{2} < SiO_{2} < SnO_{2} < PbO_{2}$ : increasing oxidising power
b.
$HF < HCl < HBr < HI$ : increasing acid strength
c.
$NH_{3} < PH_{3} < AsH_{3} < SbH_{3}$ : increasing basic strength
d.
$B < C < O < N$ : increasing first ionization enthalpy.
Correct Answer & Step-by-Step Solution Locked

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

Q50 mcq
The bond dissociation energy of $B -F$ in $BF_{3}$ is $646\,kJ$ mol $^{-1}$ whereas that of $C -F$ in $CF_{4}$ is $515\,kJ$ mol $^{-1}$ . The correct reason for higher B-F bond dissociation energy as compared to that of $C$ - $F$ is :
a.
smaller size of B-atom as compared to that of C- atom
b.
stronger $\sigma$ bond between $B$ and $F$ in $BF_{3}$ as compared to that between $C$ and $F$ in $CF_{4}$
c.
significant $p\pi -p\pi$ interaction between $B$ and $F$ in $BF_{3}$ whereas there is no possibility of such interaction between $C$ and $F$ in $CF_{4}$ .
d.
lower degree of $p\pi -p\pi$ interaction between $B$ and $F$ in $BF_{3}$ than that between $C$ and $F$ in $CF_{4}$ .
Correct Answer & Step-by-Step Solution Locked

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

Q51 mcq
Which of the following statements is incorrect regarding physissorptions ?
a.
It occurs because of vander Waal's forces.
b.
More easily liquefiable gases are adsorbed readily.
c.
Under high pressure it results into multi molecular layer on adsorbent surface.
d.
Enthalpy of adsorption $(\Delta H_{adsorption\,})$ is low and positive.
Correct Answer & Step-by-Step Solution Locked

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

Q52 mcq
The half life period of a first order chemical reaction is $6.93$ minutes. The time required for the completion of $99%$ of the chemical reaction will be $(log 2 = 0.301)$ :
a.
$230.3$ minutes
b.
$23.03$ minutes
c.
$46.06$ minutes
d.
$460.6$ minutes
Correct Answer & Step-by-Step Solution Locked

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

Q53 mcq
A binary liquid solution is prepared by mixing $n$ -heptane and ethanol. Which one of the following statements is correct regarding the behaviour of the solution?
a.
The solution formed is an ideal solution
b.
The solution is non-ideal, showing +ve deviation from Raoult's law.
c.
The solution is non-ideal, showing -ve deviation from Raoult's law.
d.
n-heptane shows +ve deviation while ethanol shows -ve deviation from Raoult's law.
Correct Answer & Step-by-Step Solution Locked

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

Q54 mcq
On the basis of the following thermochemical data: $(\Delta fG^{\circ }H^{+}_{(aq)\,} = 0)$ $H_{2}O(\ell ) \rightarrow H\rightarrow^{+}(aq) + OH^{-}(aq); \Delta H = 57.32\,kJ$ $H_{2}(\,g) + \frac{1}{2}O_{2}(\,g) \rightarrow H\rightarrow_{2}O(\ell ); \Delta H = -286.20\,kJ$ The value of enthalpy of formation of $OH^{-}$ ion at $25^{\circ }C$ is:
a.
$-22.88\,kJ$
b.
$-228.88\,kJ$
c.
$+228.88\,kJ$
d.
$-343.52\,kJ$
Correct Answer & Step-by-Step Solution Locked

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

Q55 mcq
The number of stereoisomers possible for a compound of the molecular formula $CH_{3}-CH = CH -CH(OH) -Me$ is :
a.
3
b.
2
c.
4
d.
6
Correct Answer & Step-by-Step Solution Locked

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

Q56 mcq
The set representing the correct order of ionic radius is :
a.
$Li^{+} > Be^{2+} > Na^{+} > Mg^{2+}$
b.
$Na^{+} > Li^{+} > Mg^{2+} > Be^{2+}$
c.
$Li^{+} > Na^{+} > Mg^{2+} > Be^{2+}$
d.
$Mg^{2+} > Be^{2+} > Li^{+} > Na^{+}$
Correct Answer & Step-by-Step Solution Locked

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

Q57 mcq
Which of the following pairs represents linkage isomers ?
a.
$[Cu(NH_{3})_{4}] [PtCl_{4}]$ and $[Pt(NH_{3})_{4}] [CuCl_{4}]$
b.
$[Pd(PPh_{3})_{2}(NCS)_{2}]$ and $[Pd(PPh_{3})_{2}(SCN)_{2}]$
c.
$[CO(NH_{3})_{5}NO_{3}]SO_{4}$ and $[CO(NH_{3})_{5}SO_{4}]NO_{3}$
d.
$[PtCl_{2}(NH_{3})_{4}]Br$ and $[PtBr_{2}(NH_{3})_{4}]Cl_{2}$
Correct Answer & Step-by-Step Solution Locked

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

Q58 mcq
Two liquids $X$ and $Y$ form an ideal solution. At $300\,K$ , vapour pressure of the solution containing 1 mol of $X$ and $3\,mol$ of $Y$ is $550\,mmHg$ . At the same temperature, if $1\,mol$ of $Y$ is further added to this solution, vapour pressure of the solution increases by $10\,mmHg$ . Vapour pressure (in $mmHg$ ) of $X$ and $Y$ in their pure states will be, respectively :
a.
200 and 300
b.
300 and 400
c.
400 and 600
d.
500 and 600
Correct Answer & Step-by-Step Solution Locked

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

Q59 mcq
Which of the following has an optical isomer ?
a.
$[CO(NH_{3})_{3}Cl]^{+}$
b.
$[CO(\,en\,)(NH_{3})_{2}]^{2+}$
c.
$[CO(H_{2}O)_{4}(en)]^{3+}$
d.
$[CO(en)_{2}(NH_{3})_{2}]^{3+}$
Correct Answer & Step-by-Step Solution Locked

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

Q60 mcq
The two functional groups present in a typical carbohydrate are :
a.
$-OH$ and $-COOH$
b.
$-CHO$ and $-COOH$
c.
$> C = O$ and $-OH$
d.
$-OH$ and $-CHO$
Correct Answer & Step-by-Step Solution Locked

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

Q61 mcq
Let $f(x) =x|x|$ and $g(x) = sinx$ . Statement-1 : gof is differentiable at $x= 0$ and its derivative is continuous at that point. Statement-2 : gof is twice differentiable at $x= 0$ .
a.
Statement-1 is true, Statement-2 is true; Statement-2 is a correct explanation for Statement-1
b.
Statement-1 is true, Statement-2 is true; Statement-2 is not a correct explanation for Statement-1
c.
Statement-1 is true, Statement-2 is false
d.
Statement-1 is false, Statement-2 is true
Correct Answer & Step-by-Step Solution Locked

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

Q62 mcq
If $z- \frac{4}{z} = 2$ , then the maximum value of $|z|$ is equal to
a.
$\sqrt{3}+ 1$
b.
$\sqrt{5}+ 1$
c.
2
d.
$2 + \sqrt{2}$
Correct Answer & Step-by-Step Solution Locked

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

Q63 mcq
Let the line $\frac{x-2}{3} = \frac{y-1}{-5} = \frac{z+2}{2}$ lies in the plane $x+ 3y- \alpha z+\beta = 0$ . Then $(\alpha ,\beta )$ equals
a.
$(6, -17)$
b.
$(-6, 7)$
c.
$(5, -15)$
d.
$(-5, 15)$
Correct Answer & Step-by-Step Solution Locked

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

Q64 mcq
$| | |$ $a a+ 1 a-1 a+ 1 b+ 1 c-1$ Let $a,b,c$ be such that $b(a+c) \neq 0$ . If $-b b+ 1 b-1 + a-1 b-1 c+ 1 = 0$ , then the $c c-1 c+ 1 (-1)^{n+2}a (-1)^{n+1}b (-1)^{n}c$ value of ' $n$ ' is
a.
zero
b.
any even integer
c.
any odd integer
d.
any integer
Correct Answer & Step-by-Step Solution Locked

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

Q65 mcq
The sum to the infinity of the series $1 + \frac{2}{3} + \frac{6}{3^{2}} + \frac{10}{3^{3}} + \frac{14}{3^{4}} + … …$ is
a.
2
b.
3
c.
4
d.
6
Correct Answer & Step-by-Step Solution Locked

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

Q66 mcq
If $A,B$ and $C$ are three sets such that $A\cap B=A\cap C$ and $A\cup B=A\cup C$ , then
a.
$A=B$
b.
$A=C$
c.
$B=C$
d.
$A\cap B=\phi$
Correct Answer & Step-by-Step Solution Locked

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

Q67 mcq
Let $f(x) = (x+ 1)^{2} -1,x\geq -1$ Statement-1: The set ${x:f(x) =f^{-1}(x)}= {0, -1}$ Statement-2 : $f$ is a bijection.
a.
Statement-1 is true, Statement-2 is true; Statement-2 is a correct explanation for Statement-1
b.
Statement-1 is true, Statement-2 is true; Statement-2 is not a correct explanation for Statement-1
c.
Statement-1 is true, Statement-2 is false
d.
Statement-1 is false, Statement-2 is true
Correct Answer & Step-by-Step Solution Locked

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

Q68 mcq
The shortest distance between the line $y -x = 1$ and the curve $x = y^{2}$ is
a.
$\frac{3\sqrt{2}}{8}$
b.
$\frac{2\sqrt{3}}{8}$
c.
$\frac{3\sqrt{2}}{5}$
d.
$\frac{\sqrt{3}}{4}$
Correct Answer & Step-by-Step Solution Locked

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

Q69 mcq
$||$ Three distinct points A, B and C are given in the 2 - dimensional coordinate plane such that the ratio of the distance of any one of them from the point $(1, 0)$ to the distance from the point $(-1, 0)$ is equal to $\frac{1}{3}$ . Then the circumcentre of the triangle $ABC$ is at the point
Question 69 image
a.
$(0, 0)$
b.
$(\frac{5}{4}, 0)$
c.
$(\frac{5}{2}, 0)$
d.
$(\frac{5}{3}, 0)$
Correct Answer & Step-by-Step Solution Locked

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

Q70 mcq
Given $P(x) =x^{4} +ax^{3} +bx^{2} +cx+d$ such that $x= 0$ is the only real root of $P'(x) = 0$ . If $P(-1) <P(1)$ , then in the interval $[-1, 1]$
a.
$P(-1)$ is the minimum and $P(1)$ is the maximum of $P$
b.
$P(-1)$ is not minimum but $P(1)$ is the maximum of $P$
c.
$P(-1)$ is the minimum and $P(1)$ is not the maximum of $P$
d.
neither $P(-1)$ is the minimum nor $P(1)$ is the maximum of $P$
Correct Answer & Step-by-Step Solution Locked

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

Q71 mcq
The remainder left out when $8^{2n} -(62)^{2n+1}$ is divided by 9 is
a.
0
b.
2
c.
7
d.
8
Correct Answer & Step-by-Step Solution Locked

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

Q72 mcq
Statement-1 : The variance of first $n$ even natural numbers is $\frac{n^{2}-1}{4}$ Statement-2 : The sum of first $n$ natural numbers is $\frac{n(n+1)}{2}$ and the sum of squares of first $n$ natural numbers is $\frac{n(n+1)(2n+1)}{6}$
a.
Statement-1 is true, Statement-2 is true; Statement-2 is a correct explanation for Statement-1
b.
Statement-1 is true, Statement-2 is true; Statement-2 is not a correct explanation for Statement-1
c.
Statement-1 is true, Statement-2 is false
d.
Statement-1 is false, Statement-2 is true
Correct Answer & Step-by-Step Solution Locked

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

Q73 mcq
If $P$ and $Q$ are the points of intersection of the circles $x^{2} +y^{2} + 3x+ 7y+ 2p-5 = 0$ and $x^{2} +y^{2} + 2x+ 2y- p^{2} = 0$ , then there is a circle passing through $P,Q$ and $(1, 1)$ for
a.
all values of $p$
b.
all except one value of $p$
c.
all except two values of $p$
d.
exactly one value of $p$
Correct Answer & Step-by-Step Solution Locked

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

Q74 mcq
The ellipse $x^{2} + 4y^{2} = 4$ is inscribed in a rectangle aligned with the coordinate axes, which in turn in inscribed in another ellipse that passes through the point $(4, 0)$ . Then the equation of the ellipse is
a.
$x^{2} + 16y^{2} = 16$
b.
$x^{2} + 12y^{2} = 16$
c.
$4x^{2} + 48y^{2} = 48$
d.
$4x^{2} + 64y^{2} = 48$
Correct Answer & Step-by-Step Solution Locked

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

Q75 mcq
Let $y$ be an implicit function of $x$ defined by $x^{2x} -2x^{x} coty-1 = 0$ . Then $y'(1)$ equals
a.
$-1$
b.
1
c.
$log 2$
d.
$-log 2$
Correct Answer & Step-by-Step Solution Locked

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

Q76 mcq
If $\vec{u}, v, \vec{w}$ are non-coplanar vectors and $p,\vec{q}$ are real numbers, then the equality $[3\vec{u} \bar{p}v p\vec{w}] -[p\vec{v} \vec{w} q\vec{u}] -[2\vec{w} qv q\vec{u}] = 0$ holds for
a.
exactly one value of $(p,q)$
b.
exactly two values of $(p,q)$
c.
more than two but not all values of $(p,q)$
d.
all values of $(p,q)$
Correct Answer & Step-by-Step Solution Locked

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

Q77 mcq
Let A be a $2 \times 2$ matrix Statement-1 $: adj(adjA) =A$ Statement-2 : $|adj A| = |A|$
a.
Statement-1 is true, Statement-2 is true; Statement-2 is a correct explanation for Statement-1
b.
Statement-1 is true, Statement-2 is true; Statement-2 is not a correct explanation for Statement-1
c.
Statement-1 is true, Statement-2 is false
d.
Statement-1 is false, Statement-2 is true
Correct Answer & Step-by-Step Solution Locked

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

Q78 mcq
From 6 different novels and 3 different dictionaries, 4 novels and 1 dictionary are to be selected and arranged in a row on the shelf so that the dictionary is always in the middle. Then the number of such arrangements is
a.
less than 500
b.
at least 500 but less than 750
c.
at least 750 but less than 1000
d.
at least 1000
Correct Answer & Step-by-Step Solution Locked

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

Q79 mcq
Let $A$ and $B$ denote the statements A: $cos\alpha + cos\beta + cos\gamma = 0$ B: $sin\alpha + sin\beta + sin\gamma = 0$ If $cos(\beta - \gamma ) + cos(\gamma - \alpha ) + cos(\alpha - \beta ) = - \frac{3}{2}$ , then
a.
$A$ is true and $B$ is false
b.
$A$ is false and $B$ is true
c.
both $A$ and $B$ are true
d.
both $A$ and $B$ are false
Correct Answer & Step-by-Step Solution Locked

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

Q80 mcq
One ticket is selected at random from 50 tickets numbered $00, 01, 02, … , 49$ . Then the probability that the sum of the digits on the selected ticket is 8 , given that the product of these digits is zero, equals
a.
$\frac{1}{14}$
b.
$\frac{1}{7}$
c.
$\frac{5}{14}$
d.
$\frac{1}{50}$
Correct Answer & Step-by-Step Solution Locked

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

Q81 mcq
For real $x$ , let $f(x) =x^{3} + 5x+ 1$ , then
a.
$f$ is one-one but not onto $R$
b.
$f$ is onto $R$ but not one-one
c.
$f$ is one-one and onto $R$
d.
$f$ is neither one-one nor onto $R$
Correct Answer & Step-by-Step Solution Locked

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

Q82 mcq
The lines $p(p^{2} + 1)x- y+q= 0$ and $(p^{2} + 1)^{2}x+(p^{2} + 1)y+ 2q= 0$ are perpendicular to a common line for
a.
no value of $p$
b.
exactly one value of $p$
c.
exactly two values of $p$
d.
more than two values of $p$
Correct Answer & Step-by-Step Solution Locked

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

Q83 mcq
Statement-1: $\sim (p\leftrightarrow \sim q)$ is equivalent to $p\leftrightarrow q$ . Statement-2 : $\sim (p\leftrightarrow \sim q)$ is a tautology.
a.
Statement-1 is true, Statement-2 is true; Statement-2 is a correct explanation for Statement-1
b.
Statement-1 is true, Statement-2 is true; Statement-2 is not a correct explanation for Statement-1
c.
Statement-1 is true, Statement-2 is false
d.
Statement-1 is false, Statement-2 is true
Correct Answer & Step-by-Step Solution Locked

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

Q84 mcq
$\int _{0}^{\pi }[cotx]dx, [\cdot ]$ denotes the greatest integer function, is equal to
a.
$\frac{\pi}{2}$
b.
1
c.
$-1$
d.
$-\frac{\pi}{2}$
Correct Answer & Step-by-Step Solution Locked

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

Q85 mcq
If the roots of the equation $bx^{2} +cx+a= 0$ be imaginary, then for all real values of $x$ , the expression $3b^{2}x^{2} + 6bcx+ 2c^{2}$ is
a.
greater than $4ab$
b.
less than $4ab$
c.
greater than $-4ab$
d.
less than - 4ab
Correct Answer & Step-by-Step Solution Locked

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

Q86 mcq
In a binomial distribution $B(n,p= \frac{1}{4})$ , if the probability of at least one success is greater than or equal to $\frac{9}{10}$ , then $n$ is greater than
a.
$\frac{1}{log_{10}^{4}-log_{10}^{3}}$
b.
$\frac{1}{log_{10}4+log_{10}3}$
c.
$\frac{9}{log_{10}^{4}-log_{10}3}$
d.
$\frac{4}{log_{10}^{4}-log_{10}3}$
Correct Answer & Step-by-Step Solution Locked

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

Q87 mcq
The area of the region bounded by the parabola $(y-2)^{2} =x-1$ , the tangent to the parabola at the point $(2, 3)$ and the $x$ -axis is
a.
3
b.
6
c.
9
d.
12
Correct Answer & Step-by-Step Solution Locked

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

Q88 mcq
The projections of a vector on the three coordinate axis are $6, -3, 2$ respectively. The direction cosines of the vector are
a.
$6, -3, 2$
b.
$\frac{6}{5}, -\frac{3}{5}, \frac{2}{5}$
c.
$\frac{6}{7}, -\frac{3}{7}, \frac{2}{7}$
d.
$-\frac{6}{7}, -\frac{3}{7}, \frac{2}{7}$
Correct Answer & Step-by-Step Solution Locked

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

Q89 mcq
The differential equation which represents the family of curves $y=c_{1}e^{c_{2}x}$ , where $c_{1}$ and $c_{2}$ are arbitrary constants is
a.
$y' =y^{2}$
b.
$y'' =y'y$
c.
$y\vec{y}'' =y'$
d.
$yy'' = (y')^{2}$
Correct Answer & Step-by-Step Solution Locked

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

Q90 mcq
If the mean deviation of number $1, 1 +d, 1 + 2d, … . , 1 + 100d$ from their mean is 255 , then the $d$ is equal to
a.
$10.0$
b.
$20.0$
c.
$10.1$
d.
$20.2$
Correct Answer & Step-by-Step Solution Locked

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