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JEE Main

Explore popular questions for JEE Main. This collection includes questions from Physics, Mathematics, Chemistry. They're hand picked by top teachers from a vast pool of questions including previous year JEE Main questions.

Q 1.

Correct4

Incorrect-1

An air bubble doubles its radius on raising from the bottom of water reservoir to be the surface of water in it. If the atmospheric pressure is equal to {tex} 10 { m } {/tex} of water, the height of water in the reservoir is

A

{tex} 10 m {/tex}

B

{tex} 20 m {/tex}

{tex} 70 m {/tex}

D

{tex} 80 m {/tex}

Explanation

Q 2.

Correct4

Incorrect-1

Two spherical vessel of equal volume, are connected by a{tex} \ \ n {/tex} arrow tube. The apparatus contains an ideal gas at one atmosphere and {tex} 300 K {/tex}. Now if one vessel is immersed in a bath of constant temperature {tex} 600 K {/tex} and the other in a bath of constant temperature {tex} 300 K {/tex}. Then the common pressure will be

A

{tex}1atm {/tex}

B

{tex} \frac { 4 } { 5 } a t m {/tex}

{tex} \frac { 4 } { 3 } a t m {/tex}

D

{tex} \frac { 3 } { 4 } a t m {/tex}

Explanation

Q 3.

Correct4

Incorrect-1

If pressure of {tex} C O _ { 2 } {/tex} (real gas) in a container is given by {tex} P = \frac { R T } { 2 V - b } - \frac { a } { 4 b ^ { 2 } } {/tex} then mass of the gas in container is

A

{tex}11 \ g m {/tex}

{tex} 22 \ g m {/tex}

C

{tex} 33 \ gm {/tex}

D

{tex} 44 \ gm {/tex}

Explanation

Q 4.

Correct4

Incorrect-1

A gas is enclosed in a closed pot. On keeping this pot in a train moving with high speed, the temperature of the gas

A

Will increase

B

Will decrease

Will remain the same

D

Will change according to the nature of the gas

Explanation

Q 5.

Correct4

Incorrect-1

If the {tex} r . m .s {/tex} velocity of a gas at a given temperature (Kelvin scale) is {tex} 300 \mathrm { m } / \mathrm { sec } . {/tex} What will be the {tex} \mathrm { r.m.s } {/tex} velocity of a gas having twice the molecular weight and half the temperature on Kelvin scale =

A

{tex} 300 \mathrm { m } / \mathrm { sec } {/tex}

B

{tex} 600 \mathrm { m } / \mathrm { sec } {/tex}

C

{tex} 75 \mathrm { m } / \mathrm { sec } {/tex}

{tex} 150 \mathrm { m } / \mathrm { sec } {/tex}

Explanation

Q 6.

Correct4

Incorrect-1

The ratio of two specific heats {tex} \frac { C _ { P } } { C _ { V } } {/tex} of {tex} C O {/tex} is

A

1.33

1.4

C

1.29

D

1.66

Explanation

Q 7.

Correct4

Incorrect-1

At what temperature, the mean kinetic energy of {tex} O _ { 2 } {/tex} will be the same for {tex} H _ { 2 } {/tex} molecules at {tex} - 73 ^ { \circ } \mathrm { C } {/tex}

A

{tex} 127 ^ { \circ } \mathrm { C } {/tex}

B

{tex} 527 ^ { \circ } \mathrm { C } {/tex}

{tex} - 73 ^ { \circ } \mathrm { C } {/tex}

D

{tex} - 173 ^ { \circ } \mathrm { C } {/tex}

Explanation

Q 8.

Correct4

Incorrect-1

The volume of a gas at pressure {tex} 21 \times 10 ^ { 4 } N / m ^ { 2 } {/tex} and temperature {tex} 27 ^ { \circ } \mathrm { C } {/tex} is 83 litres. If {tex} R = 8.3\ J/ \mathrm { mol } / \mathrm { K } {/tex}, then the quantity of gas in {tex} \mathrm { gm-mole } {/tex} will be

A

15

B

42

7

D

14

Explanation

Q 9.

Correct4

Incorrect-1

The pressure and temperature of an ideal gas in a closed vessel are {tex} 720\ { kPa } {/tex} and {tex} 40 ^ { \circ } { C } {/tex} respectively. If {tex} \frac { 1 } { 4 } {/tex} th of the gas is released from the vessel and the temperature of the remaining gas is raised to {tex} 353 ^ { \circ }{ C } , {/tex} the final pressure of the gas is

A

{tex} 1440 \mathrm { kPa } {/tex}

{tex} 1080 \mathrm { kPa } {/tex}

C

{tex} 720 \mathrm { kPa } {/tex}

D

{tex} 540 \mathrm { kPa } {/tex}

Explanation

Q 10.

Correct4

Incorrect-1

The energy of a gas/litre is 300 joules, then its pressure will be

A

{tex} 3 \times 10 ^ { 5 } \mathrm { N } / \mathrm { m } ^ { 2 } {/tex}

B

{tex} 6 \times 10 ^ { 5 } \mathrm { N } / \mathrm { m } ^ { 2 } {/tex}

C

{tex} 10 ^ { 5 } \mathrm { N } / \mathrm { m } ^ { 2 } {/tex}

{tex} 2 \times 10 ^ { 5 } \mathrm { N } / \mathrm { m } ^ { 2 } {/tex}

Explanation

Q 11.

Correct4

Incorrect-1

A pressure cooker contains air at 1 atm and {tex} 30 ^ { \circ } \mathrm { C } {/tex}. If the safety value of the cooler blows when the inside pressure {tex} \geq 3\ atm {/tex} , then the maximum temperature of the air, inside the cooker can be

A

{tex} 90 ^ { \circ } \mathrm { C } {/tex}

{tex} 636 ^ { \circ } \mathrm { C } {/tex}

C

{tex} 909 ^ { \circ } \mathrm { C } {/tex}

D

{tex} 363 ^ { \circ } \mathrm { C } {/tex}

Explanation

Q 12.

Correct4

Incorrect-1

From the following {tex} V - T {/tex} diagram we can conclude

A

{tex} P_{1} = P_{2} {/tex}

{tex} P_{1} > P_{2} {/tex}

C

{tex} P_{1}< P_{2} {/tex}

D

None of these

Explanation



Q 13.

Correct4

Incorrect-1

The {tex} r . m .s {/tex} velocity of a gas at a certain temperature is {tex} \sqrt { 2 } {/tex} times than that of the oxygen molecules at that temperature. The gas can be

A

{tex} H _ { 2 } {/tex}

B

{tex} H e {/tex}

{tex} C H _ { 4 } {/tex}

D

{tex} S O _ { 2 } {/tex}

Explanation

Q 14.

Correct4

Incorrect-1

One mole of an ideal monatomic gas requires {tex}210\ J{/tex} heat to raise the temperature by {tex} 10 K , {/tex} when heated at constant temperature. If the same gas is heated at constant volume to raise the temperature by {tex}10 K {/tex} then heat required is

A

{tex} 238\ J {/tex}

{tex} 126\ J {/tex}

C

{tex} 210 \ J{/tex}

D

{tex}350\ J{/tex}

Explanation

Q 15.

Correct4

Incorrect-1

When the temperature of a gas is raised from {tex} 27 ^ { \circ } \mathrm { C } {/tex} to {tex} 90 ^ { \circ } \mathrm { C } , {/tex} the percentage increase in the {tex} r . m .s {/tex} velocity of the molecules will be

{tex} 10 \% {/tex}

B

{tex} 15 \% {/tex}

C

{tex} 20 \% {/tex}

D

{tex} 17.5 \% {/tex}

Explanation

Q 16.

Correct4

Incorrect-1

Pressure versus temperature graphs of an ideal gas are as shown in figure. Choose the wrong statement

A

Density of gas is increasing in graph (i)

B

Density of gas is decreasing in graph (ii)

Density of gas is constant in graph (iii)

D

None of these

Explanation


Q 17.

Correct4

Incorrect-1

An ideal gas has an initial pressure of 3 pressure units and an initial volume of 4 volume units. The table gives the final pressure and volume of the gas (in those same units) in four, processes. Which processes start and end on the same isotherm

A

{tex} A {/tex}

B

{tex} B {/tex}

{tex} C {/tex}

D

{tex} D {/tex}

Explanation

so, final {tex}{ P }{ V }=12{/tex} Hence, option C is correct.

Q 18.

Correct4

Incorrect-1

A cylinder of fixed capacity {tex}44.8\ litre{/tex}, contains a monatomic gas at standard temperature and pressure. The amount of heat required to cylinder by {tex} 10 ^ { \circ } \mathrm { C } {/tex} will be. {tex} ( R = {/tex} universal gas constant)

A

{tex} R {/tex}

B

{tex} 10 R {/tex}

C

{tex} 20 R {/tex}

{tex} 30 R {/tex}

Explanation

Q 19.

Correct4

Incorrect-1

Suppose ideal gas equation {tex} V {/tex} follows {tex} 3VP = constant{/tex}. Initial temperature and volume of the gas are {tex} T {/tex} and {tex} V {/tex} respectively. If gas expand to {tex} 27\ V {/tex} then its temperature will be come

A

{tex} T {/tex}

{tex} 9 \ T {/tex}

C

{tex} 27 \ T {/tex}

D

{tex} T / 9 {/tex}

Explanation


Q 20.

Correct4

Incorrect-1

One mole of a monoatomic ideal gas is mixed with one mole of a diatomic ideal gas. The molar specific heat of the mixture at constant volume is

A

{tex} 8 {/tex}

B

{tex} \frac { 3 } { 2 } \ R {/tex}

{tex} 2\ R {/tex}

D

{tex} 2.5\ R {/tex}

Explanation