MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
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.
| 1351. |
Assertion : It is not possible for a system, unaided by an external agency to transfer heat from a body at lower temperature to another body at higher temperature. Reason : According to Clausius statement, ? No process is possible whose sole result is the transfer of heat from a cooled object to a hotter object. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 1352. |
A coil has L = 0.04 H and \[R=12\,\Omega \]. When it is connected to 220V, 50Hz supply the current flowing through the coil, in amperes is [Kerala PMT 2004] |
| A. | 10.7 |
| B. | 11.7 |
| C. | 14.7 |
| D. | 12.7 |
| Answer» E. | |
| 1353. |
Assertion : If three identical bulbs are connected in series as shown in figure then on closing the switches. Bulb C short circuited and hence illumination of bulbs A and B decreases. Reason : Voltage on A and B decreases |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» E. If assertion is false but reason is true. | |
| 1354. |
Calculate the work done when 1 mole of a perfect gas is compressed adiabatically. The initial pressure and volume of the gas are \[{{10}^{5}}N/{{m}^{2}}\] and 6 liter respectively. The final volume of the gas is 2 liters. Molar specific heat of the gas at constant volume is 3R/2. [Given \[{{(3)}^{5/3}}=\text{ }6.19\]] |
| A. | -957 J |
| B. | +957 J |
| C. | -805 J |
| D. | + 805 J. |
| Answer» B. +957 J | |
| 1355. |
Two radioactive substances X and Y emit \[\alpha \] and \[\beta \] particles respectively. Their disintegration constants are in the ratio 2 : 3. To have equal probabilities of getting emission of \[\alpha \] and \[\beta \] particles, the ratio of number of atoms X to that of Fat any time instant is |
| A. | 2 : 3 |
| B. | 3 : 2 |
| C. | e : 1 |
| D. | (e-1) : 1 |
| Answer» C. e : 1 | |
| 1356. |
The block of mass M moving on the frictionless horizontal surface collides with the spring of spring constant K and compresses it by length L. The maximum momentum of the block after collision is [AIEEE 2005] |
| A. | Zero |
| B. | \[\frac{M{{L}^{2}}}{K}\] |
| C. | \[\sqrt{MK}\,L\] |
| D. | \[\frac{K{{L}^{2}}}{2M}\] |
| Answer» D. \[\frac{K{{L}^{2}}}{2M}\] | |
| 1357. |
In a semiconductor, the concentration of electrons is \[8\times {{10}^{14}}/c{{m}^{3}}\]and that of the holes is \[5\times {{10}^{12}}c{{m}^{3}}.\] The semiconductor is [MP PMT 1997; RPET 1999; Kerala PET 2002] |
| A. | P-type |
| B. | N-type |
| C. | Intrinsic |
| D. | PNP-type |
| Answer» C. Intrinsic | |
| 1358. |
A simple pendulum hanging from the ceiling of a stationary lift has a time period T1. When the lift moves downward with constant velocity, the time period is T2, then [Orissa JEE 2005] |
| A. | \[{{T}_{2}}\] is infinity |
| B. | \[{{T}_{2}}>{{T}_{1}}\] |
| C. | \[{{T}_{2}}<{{T}_{1}}\] |
| D. | \[{{T}_{2}}={{T}_{1}}\] |
| Answer» C. \[{{T}_{2}}<{{T}_{1}}\] | |
| 1359. |
Two pendulums begin to swing simultaneously. If the ratio of the frequency of oscillations of the two is 7 : 8, then the ratio of lengths of the two pendulums will be [J & K CET 2005] |
| A. | 7 : 8 |
| B. | 8 : 7 |
| C. | 49 : 64 |
| D. | 64 : 49 |
| Answer» C. 49 : 64 | |
| 1360. |
The ratio of frequencies of two pendulums are 2 : 3, then their length are in ratio [DCE 2005] |
| A. | \[\sqrt{2/3}\] |
| B. | \[\sqrt{3/2}\] |
| C. | \[4/9\] |
| D. | \[9/4\] |
| Answer» E. | |
| 1361. |
A boy of mass m is sliding down a vertical pole by pressing it with a horizontal force F. If \[\mu \]is the coefficient of friction between his palms and the pole, the acceleration with which he slides down is |
| A. | \[g\] |
| B. | \[\frac{\mu F}{m}\] |
| C. | \[g+\frac{\mu F}{m}\] |
| D. | \[g-\frac{\mu F}{m}\] |
| Answer» E. | |
| 1362. |
A 40 kg slab rests on a frictionless floor as shown in the figure. A 10 kg block rests on the top of the slab. The static coefficient of friction between the block and slab is 0.60 while the kinetic friction is 0.40. The 10 kg block is acted upon by a horizontal force 100 N. If \[g=9.8\,m/{{s}^{2}},\]the resulting acceleration of the slab will be |
| A. | \[1\,m/{{s}^{2}}\] |
| B. | \[1.5\,m/{{s}^{2}}\] |
| C. | \[2\,m/{{s}^{2}}\] |
| D. | \[6\,m/{{s}^{2}}\] |
| Answer» B. \[1.5\,m/{{s}^{2}}\] | |
| 1363. |
A block A is kept on a block B. Friction between B and ground is negligible. \[{{\mu }_{s}}\] and \[{{\mu }_{K}}\] are the coefficients of static and kinetic friction between A and B, respectively. A horizontal force F is applied on A. \[{{a}_{1}}\] is the acceleration of B just before A slips on B and \[{{a}_{2}}\] is the acceleration of B after A slips on B. Assume \[{{\mu }_{s}}>{{\mu }_{K}}\]. Then |
| A. | \[{{a}_{1}}>{{a}_{2}}\] |
| B. | \[{{a}_{1}}<{{a}_{2}}\] |
| C. | \[{{a}_{1}}={{a}_{2}}\] |
| D. | None of these |
| Answer» B. \[{{a}_{1}}<{{a}_{2}}\] | |
| 1364. |
The coefficient of apparent expansion of a liquid in a copper vessel is C and in a silver vessel S. The coefficient of volume expansion of copper is \[{{\gamma }_{C}}\]. What is the coefficient of linear expansion of silver? |
| A. | \[(C+{{\gamma }_{C}}+S)/3\] |
| B. | \[(C-{{\gamma }_{C}}+S)/3\] |
| C. | \[(C+{{\gamma }_{C}}-S)/3\] |
| D. | \[(C-{{\gamma }_{C}}-S)/3\] |
| Answer» D. \[(C-{{\gamma }_{C}}-S)/3\] | |
| 1365. |
How much bigger is the volume rate of flow at the end of the tube than at the entrance in cubic meters? |
| A. | \[9\,\times \,{{10}^{-5}}\] |
| B. | \[\frac{1}{3}\times \,{{10}^{-5}}\] |
| C. | \[\frac{4}{9}\times \,{{10}^{-5}}\] |
| D. | None of these |
| Answer» D. None of these | |
| 1366. |
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 contains only \[{{O}_{2}},B\] only\[{{N}_{2}},\] and \[{{O}_{2}}\] mixture of equal quantities of \[{{O}_{2}}\] and \[{{N}_{2}}\]. If the average speed of the \[{{O}_{2}}\]molecules in vessel A is \[{{V}_{1}}\] that of the \[{{N}_{2}}\] molecules in vessel B is \[{{V}_{2}}\] then the average speed of the \[{{O}_{2}}\] molecules in vessel C is (where M is the mass of an oxygen molecule) |
| A. | \[({{V}_{1}}+{{V}_{2}})/2\] |
| B. | \[{{V}_{1}}\] |
| C. | \[{{({{V}_{1}}{{V}_{2}})}^{1/2}}\] |
| D. | \[\sqrt{3kT/M}\] |
| Answer» C. \[{{({{V}_{1}}{{V}_{2}})}^{1/2}}\] | |
| 1367. |
A body executes simple harmonic motion under the action of a force \[{{F}_{1}}\] with a time period \[\frac{4}{5}\]s. If the force is changed to\[{{F}_{2}}\], it executes S.H.M. with time period - s. If both the forces \[{{F}_{1}}\] and \[{{F}_{2}}\] act simultaneously in the same direction on the body, its time period in second is |
| A. | \[\frac{12}{25}\] |
| B. | \[\frac{7}{5}\] |
| C. | \[\frac{24}{25}\] |
| D. | \[\frac{5}{7}\] |
| Answer» B. \[\frac{7}{5}\] | |
| 1368. |
The vector \[\vec{P}=a\hat{i}+a\hat{j}+3\hat{k}\] and \[\vec{Q}=a\hat{i}-2\hat{j}-\hat{k}\] are perpendicular to each other. The positive value of a is |
| A. | 3 |
| B. | 4 |
| C. | 9 |
| D. | 13 |
| Answer» B. 4 | |
| 1369. |
A particle moves along a path ABCD as shown in the figure. Then the magnitude of net displacement of the particle from position A to D is: |
| A. | 10 m |
| B. | \[5\sqrt{2}\,m\] |
| C. | 9 m |
| D. | \[7\sqrt{2}\,m\] |
| Answer» E. | |
| 1370. |
A particle is moving with velocity 5 m/s towards east and its velocity changes to 5 m/s north in 10 seconds. Find the average acceleration in 10 seconds. |
| A. | \[\sqrt{2}N-W\] |
| B. | \[\frac{1}{\sqrt{2}}N-W\] |
| C. | \[\frac{1}{\sqrt{2}}N-E\] |
| D. | \[\sqrt{2}N-E\] |
| Answer» C. \[\frac{1}{\sqrt{2}}N-E\] | |
| 1371. |
A point object is placed at a distance of 30 cm along the principal axis of a convex lens of focal length 20 cm and aperture 4 cm. The lens is cut by a plane parallel to its principal axis and both the identical pieces are inverted and placed in contact at their vertex. The distance between the images formed is |
| A. | 4 cm |
| B. | 8 cm |
| C. | 12 cm |
| D. | 16 cm |
| Answer» D. 16 cm | |
| 1372. |
When an object is at distances x and y from a lens, a real image and a virtual image is formed respectively having same magnification. The focal length of the lens is: |
| A. | \[\frac{x+y}{2}\] |
| B. | \[x-y\] |
| C. | \[\sqrt{xy}\] |
| D. | \[x+y\] |
| Answer» B. \[x-y\] | |
| 1373. |
A concave mirror gives an image three times as large as the object placed at a distance of \[20cm\] from it. For the image to be real, the focal length should be [SCRA 1998; JIPMER 2000] |
| A. | \[10cm\] |
| B. | \[15cm\] |
| C. | \[20cm\] |
| D. | \[30cm\] |
| Answer» C. \[20cm\] | |
| 1374. |
Due to 10 ampere of current flowing in a circular coil of 10 cm radius, the magnetic field produced at its centre is \[3.14\times {{10}^{-3}}\,Weber/{{m}^{2}}\]. The number of turns in the coil will be [MP PET 1996] |
| A. | 5000 |
| B. | 100 |
| C. | 50 |
| D. | 25 |
| Answer» D. 25 | |
| 1375. |
The minimum distance between the object and its real image for concave mirror is [RPMT 1999] |
| A. | f |
| B. | 2f |
| C. | 4f |
| D. | Zero |
| Answer» E. | |
| 1376. |
An object is placed at \[20cm\] from a convex mirror of focal length \[10\,cm.\] The image formed by the mirror is [JIPMER 1999] |
| A. | Real and at \[20\,cm\] from the mirror |
| B. | Virtual and at \[20\,cm\] from the mirror |
| C. | Virtual and at \[20/3\,cm\] from the mirror |
| D. | Real and at \[20/3\,cm\] from the mirror |
| Answer» D. Real and at \[20/3\,cm\] from the mirror | |
| 1377. |
Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light. [AIIMS 1997] |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 1378. |
Assertion : The focal length of the mirror is f and distance of the object from the focus is u, the magnification of the mirror is f / u. Reason : Magnification \[=\frac{\text{Size of image}}{\text{Size of object}}\] [AIIMS 1994] |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 1379. |
Assertion : Different colours travel with different speed in vacuum. Reason : Wavelength of light depends on refractive index of medium. [AIIMS 1998] |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» F. | |
| 1380. |
A wire mesh consisting of very small squares is viewed at a distance of 8 cm through a magnifying converging lens of focal length 10 cm, kept close to the eye. The magnification produced by the lens is |
| A. | 5 |
| B. | 8 |
| C. | 10 |
| D. | 20 |
| Answer» B. 8 | |
| 1381. |
For an ac circuit \[V=15\sin \omega t\] and \[I=20\cos \omega t\] the average power consumed in this circuit is [RPET 1999] |
| A. | 300 Watt |
| B. | 150 Watt |
| C. | 75 Watt |
| D. | zero |
| Answer» E. | |
| 1382. |
The maximum spectral emissive power for a black body at temperature 5000K is obtained at\[{{\lambda }_{m}}=6000\overset{o}{\mathop{A}}\,.\] If the temperature is increased by 10% then decrease in \[{{\lambda }_{m}}\] will be (approximately) |
| A. | 0.035 |
| B. | 7.5% |
| C. | 0.1 |
| D. | 0.05 |
| Answer» D. 0.05 | |
| 1383. |
Direction: In the following questions, more than one of one answers given are correct. Select the correct answers and mark it according to the following codes: A cane is taken out from a refrigerator at \[0{}^\circ C\]. The atmospheric temperature is \[25{}^\circ C\]. If \[{{t}_{1}}\] is the time taken to heat from \[0{}^\circ C\] to \[5{}^\circ C\] and \[{{t}_{2}}\] is the time taken from \[10{}^\circ C\] to \[15{}^\circ C,\] then the wrong statements are to \[{{15}^{o}}C,~\] then the wrong statements are (1) \[{{t}_{1}}>{{t}_{2}}\] (2) \[{{t}_{1}}={{t}_{2}}\] (3) There is no relation (4) \[{{t}_{1}} |
| A. | 1, 2 and 3 are correct |
| B. | 1 and 2 are correct |
| C. | 2 and 4 are correct |
| D. | 1 and 3 are correct |
| Answer» B. 1 and 2 are correct | |
| 1384. |
Direction: In the following questions, more than one of one answers given are correct. Select the correct answers and mark it according to the following codes: The rate of loss of heat from a body cooling under conditions of forced convection is proportional to its (1) surface area (2) excess of temperature over that of surrounding (3) heat capacity (4) absolute temperature Codes: |
| A. | 1, 2 and 3 are correct |
| B. | 1 and 2 are correct |
| C. | 2 and 4 are correct |
| D. | 1 and 3 are correct |
| Answer» B. 1 and 2 are correct | |
| 1385. |
At which of the following temperatures, the value of surface tension of water is minimum [MP PMT/PET 1998] |
| A. | \[{{4}^{o}}C\] |
| B. | \[{{25}^{o}}C\] |
| C. | \[{{50}^{o}}C\] |
| D. | \[{{75}^{o}}C\] |
| Answer» E. | |
| 1386. |
110 joules of heat is added to a gaseous system, whose internal energy is 40J; then the amount of external work done is |
| A. | 150 J |
| B. | 70 J |
| C. | 110 J |
| D. | 40 J |
| Answer» C. 110 J | |
| 1387. |
Assertion : A large soap bubble expands while a small bubble shrinks, when they are connected to each other by a capillary tube. Reason : The excess pressure inside bubble (or drop) is inversely proportional to the radius. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 1388. |
Consider a gas with density \[\rho \] and \[\bar{c}\] as the root mean square velocity of its molecules contained in a volume. If the system moves as whole with velocity v, then the pressure exerted by the gas is |
| A. | \[\frac{1}{3}\rho \,{{\bar{c}}^{2}}\] |
| B. | \[\frac{1}{3}\rho {{(c+v)}^{2}}\] |
| C. | \[\frac{1}{3}\rho {{(\bar{c}-v)}^{2}}\] |
| D. | \[\frac{1}{3}\rho {{({{c}^{-2}}-v)}^{2}}\] |
| Answer» B. \[\frac{1}{3}\rho {{(c+v)}^{2}}\] | |
| 1389. |
The time average of the kinetic energy of one molecule of a gas taken over a long period of time |
| A. | Is proportional to the square root of the absolute temperature of the gas |
| B. | Is proportional to the absolute temperature of the gas |
| C. | Is proportional to the square of the absolute temperature of the gas |
| D. | Does not depend upon the absolute temperature of the gas |
| Answer» C. Is proportional to the square of the absolute temperature of the gas | |
| 1390. |
The pressure exerted by the gas on the walls of the container because |
| A. | It loses kinetic energy |
| B. | It sticks with the walls |
| C. | On collision with the walls there is a change in momentum |
| D. | It is accelerated towards the walls |
| Answer» D. It is accelerated towards the walls | |
| 1391. |
If the density of the material increases, the value of Young's modulus |
| A. | Increases |
| B. | Decreases |
| C. | First increases then decreases |
| D. | First decreases then increases |
| Answer» B. Decreases | |
| 1392. |
Molybdenum is used as a target element for production of X-rays because it is [CPMT 1980; RPET 1999] |
| A. | A heavy element and can easily absorb high velocity electrons |
| B. | A heavy element with a high melting point |
| C. | An element having high thermal conductivity |
| D. | Heavy and can easily deflect electrons |
| Answer» C. An element having high thermal conductivity | |
| 1393. |
A lamp consumes only 50% of peak power in an a.c. circuit. What is the phase difference between the applied voltage and the circuit current [MP PMT 2004] |
| A. | \[\frac{\pi }{6}\] |
| B. | \[\frac{\pi }{3}\] |
| C. | \[\frac{\pi }{4}\] |
| D. | \[\frac{\pi }{2}\] |
| Answer» C. \[\frac{\pi }{4}\] | |
| 1394. |
A wire extends by 1 mm when a force is applied. Double the force is applied to another wire of same material and length but half the radius of cross-section. The elongation of the wire in mm will be [EAMCET 1986] |
| A. | 8 |
| B. | 4 |
| C. | 2 |
| D. | 1 |
| Answer» B. 4 | |
| 1395. |
Which one of the following pairs of quantities and their units is a proper match |
| A. | Electric field ?\[Coulomb/m\] |
| B. | Magnetic flux ? \[Weber\] |
| C. | Power ? Farad |
| D. | Capacitance ? Henry |
| Answer» C. Power ? Farad | |
| 1396. |
The phase difference between the two particles situated on both the sides of a node is [MP PET 2002] |
| A. | 0° |
| B. | 90° |
| C. | 180° |
| D. | 360° |
| Answer» D. 360° | |
| 1397. |
Which of the property makes difference between progressive and stationary waves [MP PMT 1987] |
| A. | Amplitude |
| B. | Frequency |
| C. | Propagation of energy |
| D. | Phase of the wave |
| Answer» D. Phase of the wave | |
| 1398. |
Assertion : The frequency of a second pendulum in an elevator moving up with an acceleration half the acceleration due to gravity is 0.612 s?1. Reason : The frequency of a second pendulum does not depend upon acceleration due to gravity. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» D. If the assertion and reason both are false. | |
| 1399. |
Assertion : Damped oscillation indicates loss of energy. Reason : The energy loss in damped oscillation may be due to friction, air resistance etc. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» C. If assertion is true but reason is false. | |
| 1400. |
A 500 kg crane takes a turn of radius 50 m with velocity of 36 km/hr. The centripetal force is [Pb. PMT 2003] |
| A. | 1200 N |
| B. | 1000 N |
| C. | 750 N |
| D. | 250 N |
| Answer» C. 750 N | |