MCQOPTIONS
Saved Bookmarks
This section includes 12583 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.
| 2351. |
One liter of oxygen at a pressure of 1 atm, and 2 liters of nitrogen at a pressure of 0.5 atm. Are introduced in the vessel of 1 liter capacity, without any change in temperature. The total pressure would be |
| A. | 1.5 atm. |
| B. | 0.5 atm. |
| C. | 2.0 atm. |
| D. | 1.0 atm. |
| Answer» D. 1.0 atm. | |
| 2352. |
Which of the following will have maximum total kinetic energy at temperature 300K? |
| A. | \[1kg{{H}_{2}}\] |
| B. | \[1kgHe\] |
| C. | \[\frac{1}{2}1kg{{H}_{2}}+\frac{1}{2}1kgHe\] |
| D. | \[\frac{1}{4}1kg{{H}_{2}}+\frac{3}{4}1kgHe\] |
| Answer» B. \[1kgHe\] | |
| 2353. |
If the molecules in a tank of hydrogen have the same RMS speed as the molecules in another tank of oxygen, we may be sure that |
| A. | the pressures are the same |
| B. | the hydrogen is at the higher temperature |
| C. | the temperatures are the same |
| D. | the oxygen is at the higher temperature |
| Answer» E. | |
| 2354. |
Air is pumped into an automobile tube up to a pressure of 200 kPa in the morning when the air temperature is \[22{}^\circ C.\] During the day, temperature rises to \[42{}^\circ C\] and the tube expands by 2%. The pressure of the air in the tube at this temperature, will be approximately |
| A. | 212 kPa |
| B. | 209 kPa |
| C. | 206 kPa |
| D. | 200 kPa |
| Answer» C. 206 kPa | |
| 2355. |
A gas at \[27{}^\circ C\] temperature and 30 atmospheric pressure is allowed to expand to the atmospheric pressure. If the volume becomes 10 times its initial volume, then the final temperature becomes |
| A. | \[100{}^\circ C\] |
| B. | \[173{}^\circ C\] |
| C. | \[273{}^\circ C\] |
| D. | \[-173{}^\circ C\] |
| Answer» E. | |
| 2356. |
The equation of state for 5 g of oxygen at a pressure P and temperature T, when occupying a volume V, will be where R is the gas constant. |
| A. | \[PV=(5/16)RT~~\] |
| B. | \[PV=(5/32)RT\] |
| C. | \[PV=5RT~\] |
| D. | \[PV=(5/2)RT\] |
| Answer» C. \[PV=5RT~\] | |
| 2357. |
One mole of an ideal gas undergoes a process\[P=\frac{{{P}_{0}}}{1+{{\left( \frac{{{V}_{0}}}{V} \right)}^{2}}}\] Here \[{{P}_{0}}\] and \[{{V}_{0}}\] are constant. Change in temperature of the gas when volume is changed from \[V={{V}_{0}}\] to \[V=2{{V}_{0}}\] |
| A. | \[\frac{-2{{P}_{0}}{{V}_{0}}}{5R}\] |
| B. | \[\frac{11{{P}_{0}}{{V}_{0}}}{10R}\] |
| C. | \[\frac{-5{{P}_{0}}{{V}_{0}}}{10R}\] |
| D. | \[{{P}_{0}}{{V}_{0}}\] |
| Answer» C. \[\frac{-5{{P}_{0}}{{V}_{0}}}{10R}\] | |
| 2358. |
In the given (V - T) diagram, what is the relation between pressure \[{{P}_{1}}\] and\[{{P}_{2}}\]? |
| A. | \[{{P}_{2}}>{{P}_{1}}\] |
| B. | \[{{P}_{2}}<{{P}_{1}}\] |
| C. | Cannot be predicted |
| D. | \[{{P}_{2}}={{P}_{1}}\] |
| Answer» C. Cannot be predicted | |
| 2359. |
The maximum attainable temperature of ideal gas in the process \[P={{P}_{0}}-\alpha {{V}^{2}}\] where \[{{P}_{0}}\]and \[\alpha \] are +ve constants. |
| A. | \[\frac{2{{P}_{0}}}{3nR}{{\left( \frac{{{P}_{0}}}{3\alpha } \right)}^{1/2}}\] |
| B. | \[\frac{{{P}_{0}}}{2nR}{{\left( \frac{2{{P}_{0}}}{3\alpha } \right)}^{1/2}}\] |
| C. | \[\frac{2nR}{{{P}_{0}}}{{\left( \frac{2{{P}_{0}}}{3\alpha } \right)}^{1/2}}\] |
| D. | \[\frac{2{{P}_{0}}}{nR}{{\left( \frac{{{P}_{0}}}{2\alpha } \right)}^{1/2}}\] |
| Answer» B. \[\frac{{{P}_{0}}}{2nR}{{\left( \frac{2{{P}_{0}}}{3\alpha } \right)}^{1/2}}\] | |
| 2360. |
An air bubble of volume \[{{v}_{0}}\] is released by a fish at a depth h in a lake. The bubble rises to the standard atmospheric pressure above the lake. The volume of the bubble just before touching the surface will be (density of water is p) |
| A. | \[{{v}_{0}}\] |
| B. | \[{{v}_{0}}\left( \rho gh/p \right)\] |
| C. | \[{{N}_{2}}\] |
| D. | \[{{v}_{0}}\left( 1+\frac{\rho gh}{p} \right)\] |
| Answer» E. | |
| 2361. |
A closed hollow insulated cylinder is filled with gas at \[0{}^\circ C\]and also contains an insulated piston of negligible weight and negligible thickness at the middle point. The gas on one side of the piston is heated to \[100{}^\circ C.\]If the piston moves 5 cm, the length of the hollow cylinder is |
| A. | 13.65 cm |
| B. | 27.3 cm |
| C. | 38.6 cm |
| D. | 64.6 cm |
| Answer» E. | |
| 2362. |
The mean free path of molecules of a gas, (radius |
| A. | \[{{r}^{3}}\] |
| B. | \[{{r}^{2}}\] |
| C. | \[r\] |
| D. | \[\sqrt{r}\] |
| Answer» C. \[r\] | |
| 2363. |
Three containers of the same volume contain three different gases. The masses of the molecules are \[{{m}_{1}},{{m}_{2}}\]and \[{{m}_{3}}\]the number of\[{{N}_{1}}\], \[{{N}_{2}}\] and \[{{N}_{3}}.\] The gas pressure in the containers \[{{P}_{1}},{{P}_{2}}\] and \[{{P}_{3}}\] respectively. All the gases are now mixed and put in one of these containers. The pressure P of the mixture will be |
| A. | \[P<\left( {{P}_{1}}+{{P}_{2}}+{{P}_{3}} \right)\] |
| B. | \[P=\frac{{{P}_{1}}+{{P}_{2}}+{{P}_{3}}}{3}\] |
| C. | \[P={{P}_{1}}+{{P}_{2}}+{{P}_{3}}\] |
| D. | \[P>\left( {{P}_{1}}+{{P}_{2}}+{{P}_{3}} \right)\] |
| Answer» D. \[P>\left( {{P}_{1}}+{{P}_{2}}+{{P}_{3}} \right)\] | |
| 2364. |
The temperature of an air bubble while rising from bottom to surface of a lake remains constant but its diameter is doubled if the pressure on the surface is equal to h meter of mercury column and relative density of mercury is \[\rho \] then the depth of lake in meter is |
| A. | \[2\rho h\] |
| B. | \[4\rho h\] |
| C. | \[8\rho h\] |
| D. | \[7\rho h\] |
| Answer» E. | |
| 2365. |
The average translational energy and the rms speed of molecules in a sample of oxygen gas at 300 K are \[6.21\text{ }\times \text{ }{{10}^{-21}}\text{ }J\] and 484 m/s respectively The corresponding values at 600 K are nearly (assuming ideal gas behavior) |
| A. | \[12.42\times {{10}^{-21}}J,928m/s\] |
| B. | \[8.78\times {{10}^{-21}}J,684m/s\] |
| C. | \[6.21\times {{10}^{-21}}J,968m/s\] |
| D. | \[12.42\times {{10}^{-21}}J,684m/s\] |
| Answer» E. | |
| 2366. |
A perfect gas at \[27{}^\circ C\] is heated at constant pressure so as to double its volume. The final temperature of the gas will be, close to |
| A. | (a)\[327{}^\circ C\] |
| B. | \[200{}^\circ C\] |
| C. | \[54{}^\circ C\] |
| D. | \[300{}^\circ C\] |
| Answer» B. \[200{}^\circ C\] | |
| 2367. |
At \[10{}^\circ C\] the value of the density of a fixed mass of an ideal gas divided by its pressure is x. At \[110{}^\circ C\]this ratio is: |
| A. | x |
| B. | \[\frac{383}{283}x\] |
| C. | \[\frac{10}{110}x\] |
| D. | \[\frac{283}{383}x\] |
| Answer» E. | |
| 2368. |
The average translational kinetic energy of \[{{O}_{2}}\](relative molar mass 32) molecules at a particular temperature is 0.048 eV. The translational kinetic energy of \[{{N}_{2}}\] (relative molar mass 28) molecules in eV at the same temperature is |
| A. | 0.0015 |
| B. | 0.003 |
| C. | 0.048 |
| D. | 0.768 |
| Answer» D. 0.768 | |
| 2369. |
The figure shows graph of pressure and volume of a gas at two different temperatures \[{{T}_{1}}\]and\[{{T}_{2}}\]. Which of the following inferences is correct? |
| A. | \[{{T}_{1}}>{{T}_{2}}\] |
| B. | \[{{T}_{1}}={{T}_{2}}\] |
| C. | \[{{T}_{1}}<{{T}_{2}}\] |
| D. | None of these |
| Answer» D. None of these | |
| 2370. |
The absolute gas temperature at which the root mean square speed of helium molecules exceeds their most probable speed by 200 m/s is |
| A. | 110.2 K |
| B. | 90.2 K |
| C. | 190.2 K |
| D. | 100.2 K |
| Answer» D. 100.2 K | |
| 2371. |
A balloon contains \[1500\text{ }{{m}^{3}}\] of helium at \[27{}^\circ C\]and 4 atmospheric pressure. The volume of helium at \[-3{}^\circ C\] temperature and 2 atmospheric pressure will, |
| A. | \[1500{{m}^{3}}~\] |
| B. | \[~1700{{m}^{3}}\] |
| C. | \[1900{{m}^{3}}\] |
| D. | \[~2700{{m}^{3}}\] |
| Answer» E. | |
| 2372. |
Boyle' law is applicable for an |
| A. | adiabatic process. |
| B. | isothermal process. |
| C. | isobaric process. |
| D. | isochoric process |
| Answer» C. isobaric process. | |
| 2373. |
The density (p)versus pressure (P) of a given mass of an ideal gas is shown at two temperatures\[~{{T}_{1}}\] and \[~{{T}_{2}}\] Then relation between \[~{{T}_{1}}\] and \[~{{T}_{2}}\] may be |
| A. | \[{{T}_{1}}>{{T}_{2}}\] |
| B. | \[{{T}_{2}}>{{T}_{1}}\] |
| C. | \[{{T}_{1}}={{T}_{2}}\] |
| D. | All the three are possible |
| Answer» C. \[{{T}_{1}}={{T}_{2}}\] | |
| 2374. |
N molecules each of mass m of a gas A and 2N molecules each of mass 2m of gas B are contained in the same vessel which is maintained at temperature T. The mean square velocity of molecules of B type is \[{{v}^{2}}\] and the mean square rectangular component of the velocity of A type is denoted by \[{{\omega }^{2}}.\] Then \[6.21\text{ }\times \text{ }{{10}^{-21}}\text{ }J\]is |
| A. | 2 |
| B. | 1 |
| C. | 1/3 |
| D. | 44257 |
| Answer» E. | |
| 2375. |
Three closed vessels A, B and C are at the same temperature T and contain gases which obey the Maxwellian distribution of velocities. Vessel A contain only\[{{O}_{2}}\], B only \[{{N}_{2}}\] and C a mixture of equal quantities of \[{{O}_{2}}\] and \[{{N}_{2}}\]. If the average speed of the \[{{O}_{2}}\] molecules in vessel A is that of the \[{{N}_{2}}\] molecules in vessel B is \[{{v}_{2}},\] the average speed of the \[{{O}_{2}}\] molecules in vessel C is |
| A. | \[\frac{{{v}_{1}}+{{v}_{2}}}{2}\] |
| B. | \[{{v}_{1}}\] |
| C. | \[{{\left( {{v}_{1}}.{{v}_{2}} \right)}^{\frac{1}{2}}}\] |
| D. | \[\sqrt{\frac{3kT}{M}}\] |
| Answer» C. \[{{\left( {{v}_{1}}.{{v}_{2}} \right)}^{\frac{1}{2}}}\] | |
| 2376. |
In an ideal gas at temperature T, the average force that a molecule applies on the walls of a closed container depends on T as\[{{\text{T}}^{\text{q}}}\]. A good estimate for q is: |
| A. | \[\frac{1}{2}\] |
| B. | 2 |
| C. | 1 |
| D. | \[\frac{1}{4}\] |
| Answer» D. \[\frac{1}{4}\] | |
| 2377. |
One gram mole of nitrogen at \[27{}^\circ C\]and 1 aim pressure is contained in a vessel and the molecules are moving with their rms speed. The number of collisions per second which the vessel's wall is |
| A. | \[2\times {{10}^{27}}\] |
| B. | \[~2\times {{10}^{20}}\] |
| C. | \[2\times {{10}^{10}}\] |
| D. | \[~2\times {{10}^{24}}\] |
| Answer» B. \[~2\times {{10}^{20}}\] | |
| 2378. |
Four molecules have speeds 2 km/sec, 3 km/sec, 4 km/sec and 5 km/sec. The root mean square speed of these molecules (in km/sec) is |
| A. | \[\sqrt{54/4}\] |
| B. | \[\sqrt{54/2}\] |
| C. | 3.5 |
| D. | \[3\sqrt{3}\] |
| Answer» B. \[\sqrt{54/2}\] | |
| 2379. |
Five gas molecules chosen at random are found to have speeds of 500, 600, 700, 800 and 900 m/s |
| A. | the root mean square speed and the average |
| B. | the root mean square speed is 14 m/s higher than the average speed. |
| C. | the root mean square speed is 14 m/s lower than the average speed. |
| D. | the root mean square speed is \[\sqrt{14}\text{ m/s}\]higher than the average speed. |
| Answer» C. the root mean square speed is 14 m/s lower than the average speed. | |
| 2380. |
Relation between pressure (P) and energy (E) of gas is |
| A. | \[P=\frac{2}{3}E\] |
| B. | \[P=\frac{1}{3}E\] |
| C. | \[P=\frac{1}{2}E\] |
| D. | \[P=3E\] |
| Answer» B. \[P=\frac{1}{3}E\] | |
| 2381. |
Pressure versus temperature graph of an ideal gas of equal number of moles of different volumes are plotted as shown in figure. Choose the correct alternative |
| A. | \[{{V}_{1}}={{V}_{2}};{{V}_{3}}={{V}_{4}}\text{ and }{{V}_{2}}>{{V}_{3}}\] |
| B. | \[{{V}_{1}}={{V}_{2}};{{V}_{3}}={{V}_{4}}\text{ and }{{V}_{2}}<{{V}_{3}}\] |
| C. | \[{{V}_{1}}={{V}_{2}}={{V}_{3}}={{V}_{4}}\] |
| D. | \[{{V}_{4}}>{{V}_{3}}>{{V}_{2}}>{{V}_{1}}\] |
| Answer» B. \[{{V}_{1}}={{V}_{2}};{{V}_{3}}={{V}_{4}}\text{ and }{{V}_{2}}<{{V}_{3}}\] | |
| 2382. |
The quantity of gas in a closed vessel is halved and the velocities of its molecules are doubled. The final pressure of the gas will be |
| A. | P |
| B. | 2P |
| C. | P/2 |
| D. | 4P |
| Answer» C. P/2 | |
| 2383. |
Modern vacuum pumps can evacuate a vessel down to a pressure of \[4.0\times {{10}^{-15}}\text{ }atm.\]at room temperature (300 K). Taking , \[1\text{ }atm=105\text{ }Pa\]and \[{{N}_{avogadro}}=6\times {{10}^{23}}mol{{e}^{-1}},\] the mean distance between molecules of gas in an evacuated vessel will be of the order of: |
| A. | 0.2 urn |
| B. | 0.2 mm |
| C. | 0.2 cm |
| D. | 0.2 nm |
| Answer» C. 0.2 cm | |
| 2384. |
At what temperature is the r. m. s velocity of a hydrogen molecule equal to that of an oxygen molecule at \[47{}^\circ C\]? |
| A. | 80 K |
| B. | -73 K |
| C. | 3 K |
| D. | 20 K |
| Answer» E. | |
| 2385. |
A nitrogen molecule has some rms speed at \[0{}^\circ C\]on the surface of the earth. With this speed, it goes straight up. If there is no collisions with other molecules, the molecule will rise up to a height of |
| A. | 82 km |
| B. | 12.4 km |
| C. | 10.6 km |
| D. | 152 km |
| Answer» C. 10.6 km | |
| 2386. |
The density of a gas is \[6\times {{10}^{-2}}kg/{{m}^{3}}\] and the root mean square velocity of the gas molecules is 500 m/s. The pressure exerted by the gas on the walls of the vessel is |
| A. | \[5\times {{10}^{3}}N/{{m}^{2}}\] |
| B. | \[1.1\times {{10}^{-4}}N/{{m}^{2}}\] |
| C. | \[0.83\times {{10}^{-4}}N/{{m}^{2}}~\] |
| D. | \[30N/{{m}^{2}}\] |
| Answer» B. \[1.1\times {{10}^{-4}}N/{{m}^{2}}\] | |
| 2387. |
Figure shows a parabolic graph between T and 1/V for a mixture of a gas undergoing an adiabatic process. What is the ratio of \[{{V}_{rms}}\] of molecules and speed of sound in mixture? |
| A. | \[\sqrt{3/2}\] |
| B. | \[\sqrt{2}\] |
| C. | \[\sqrt{2/3}\] |
| D. | \[\sqrt{3}\] |
| Answer» C. \[\sqrt{2/3}\] | |
| 2388. |
The temperature of an ideal gas is increased from 120 K to 480 K. If at 120 K the root-mean-square velocity of the gas molecules is v, at 480 K it becomes |
| A. | 4v |
| B. | 2v |
| C. | v/2 |
| D. | v/4 |
| Answer» C. v/2 | |
| 2389. |
Why does the pressure of an ideal gas increase when it is heated at constant volume? |
| A. | The gas molecules expand |
| B. | The molecules move at the same speed, but |
| C. | The molecules move faster and hit the walls more often |
| D. | The number of molecules of gas increases |
| Answer» D. The number of molecules of gas increases | |
| 2390. |
Helium gas is filled in a closed vessel (having negligible thermal expansion coefficient) when it is heated from 300 K to 600 K, then average kinetic energy of helium atom will be |
| A. | \[\sqrt{2}\] times |
| B. | 2 times |
| C. | unchanged |
| D. | half |
| Answer» C. unchanged | |
| 2391. |
The pressure of a gas is raised from \[27{}^\circ C\]to \[927{}^\circ C.\]The root mean square speed is |
| A. | \[\sqrt{\left( 927/27 \right)}\] times the earlier value |
| B. | remain the same |
| C. | gets halved |
| D. | get doubled |
| Answer» E. | |
| 2392. |
Consider a gas with density \[\rho \] and \[\overline{c}\] as the root mean square velocity of its molecules contained in a volume. If the system moves as whole with velocity, then the pressure exerted by the gas is |
| A. | \[\frac{1}{3}\rho {{\bar{c}}^{2}}\] |
| B. | \[\frac{1}{3}\rho {{\left( c+\nu \right)}^{2}}\] |
| C. | \[\frac{1}{3}\rho {{\left( \bar{c}-\nu \right)}^{2}}\] |
| D. | \[\frac{1}{3}\rho {{\left( {{{\bar{c}}}^{2}}-\nu \right)}^{2}}\] |
| Answer» B. \[\frac{1}{3}\rho {{\left( c+\nu \right)}^{2}}\] | |
| 2393. |
At room temperature a diatomic gas is found to have an r. m. s. speed of \[1930\text{ }m{{s}^{-1}}\]. The gas is: |
| A. | \[{{H}_{2}}\] |
| B. | \[C{{l}_{2}}\] |
| C. | \[{{O}_{2}}\] |
| D. | \[{{F}_{2}}\] |
| Answer» B. \[C{{l}_{2}}\] | |
| 2394. |
For a gas sample with Np number of molecules, function N(V) is given by: \[N\left( V \right)=\frac{dN}{dV}=\left[ \frac{3{{F}_{0}}}{V_{0}^{3}} \right]{{V}^{2}}\] for \[0\le V\le {{V}_{0}}\]and \[N\left( V \right)=0\]for \[V>{{V}_{0}}\] Where \[dN\] is number of molecules in speed range V to \[V+dV.\]The rms speed of the gas molecule is |
| A. | \[\sqrt{\frac{2}{5}}{{V}_{0}}\] |
| B. | \[\sqrt{\frac{3}{5}}{{V}_{0}}\] |
| C. | \[\sqrt{2}{{V}_{0}}\] |
| D. | \[\sqrt{3}{{V}_{0}}\] |
| Answer» C. \[\sqrt{2}{{V}_{0}}\] | |
| 2395. |
In kinetic theory of gases, which of the following statement regarding elastic collisions of the molecules is wrong? |
| A. | Kinetic energy is lost in collisions |
| B. | Kinetic energy remains constant in collision |
| C. | Momentum is conserved in collision |
| D. | Pressure of the gas remains constant in collisions |
| Answer» D. Pressure of the gas remains constant in collisions | |
| 2396. |
The velocity of sound in air is \[332\text{ }m\text{ }{{s}^{-1}}\] at NTP. Find the rms speed of air molecules at NTP. \[\left( \gamma =1.41 \right)\] |
| A. | \[484\text{ }m{{s}^{-1}}\] |
| B. | \[418\text{ }m{{s}^{-1}}\] |
| C. | \[248\text{ }m{{s}^{-1}}\] |
| D. | \[382\text{ }m{{s}^{-1}}\] |
| Answer» B. \[418\text{ }m{{s}^{-1}}\] | |
| 2397. |
A system consists of two stars of equal masses that revolve in a circular orbit about a centre of mass midway between them. Orbital speed of each star is v and period is T. Find the mass M of each star (G is gravitational constant) |
| A. | \[\frac{2G{{v}^{3}}}{\pi T}\] |
| B. | \[\frac{{{v}^{3}}T}{\pi G}\] |
| C. | \[\frac{{{v}^{3}}T}{2\pi G}\] |
| D. | \[\frac{2T{{v}^{3}}}{\pi G}\] |
| Answer» E. | |
| 2398. |
Infinite number of masses, each 1 kg are placed along the x-axis \[\operatorname{at} x=\pm 1 m, \pm 2m, \pm 4m, \pm \]\[8m, \pm 16M\ldots \] the magnitude of the resultant gravitational potential in terms of gravitational constant G at the or g in \[(x=0)\] is |
| A. | G/2 |
| B. | G |
| C. | 2G |
| D. | 4G |
| Answer» D. 4G | |
| 2399. |
The gravitational field due to a mass distribution is \[\operatorname{E}=K/{{x}^{3}}\]in the x-direction. (K is a constant). Taking the gravitational potential to be zero at infinity, its value at a distance x is |
| A. | \[K/x\] |
| B. | \[K/2x\] |
| C. | \[\operatorname{K}/{{x}^{2}}\] |
| D. | \[\operatorname{K}/2{{x}^{2}}\] |
| Answer» E. | |
| 2400. |
The gravitational field in a region is given by\[\vec{g} =5N/kg\hat{i}+12N/kg\hat{j}\]. The change in the gravitational potential energy of a particle of mass 1 kg when it is taken from the origin to a point \[(7m,-3m)\] is: |
| A. | \[71\text{ }J\] |
| B. | \[13\sqrt{58}J\] |
| C. | \[-71\text{ }J\] |
| D. | \[1\text{ }J\] |
| Answer» E. | |