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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.
| 10901. |
A man standing on a cliff claps his hand hears its echo after 1 sec. If sound is reflected from another mountain and velocity of sound in air is 340 m/sec. Then the distance between the man and reflection point is [RPET 2000] |
| A. | 680 m |
| B. | 340 m |
| C. | 85 m |
| D. | 170 m |
| Answer» E. | |
| 10902. |
Speed of sound at constant temperature depends on [RPET 2000; AIIMS 1998] |
| A. | Pressure |
| B. | Density of gas |
| C. | Above both |
| D. | None of the above |
| Answer» E. | |
| 10903. |
The speed of a wave in a certain medium is 960 m/s. If 3600 waves pass over a certain point of the medium in 1 minute, the wavelength is [MP PMT 2000] |
| A. | 2 metres |
| B. | 4 metres |
| C. | 8 metres |
| D. | 16 metres |
| Answer» E. | |
| 10904. |
Assertion : In the following circuit the potential drop across the resistance is zero. Reason : The given resistance has low value. |
| 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. | |
| 10905. |
A block of mass m initially at rest is dropped from a height h on to a spring of force constant k. the maximum compression in the spring is x then [BCECE 2005] |
| A. | \[mgh=\frac{1}{2}k{{x}^{2}}\] |
| B. | \[mg(h+x)=\frac{1}{2}k{{x}^{2}}\] |
| C. | \[mgh=\frac{1}{2}k{{(x+h)}^{2}}\] |
| D. | \[mg(h+x)=\frac{1}{2}k{{(x+h)}^{2}}\] |
| Answer» C. \[mgh=\frac{1}{2}k{{(x+h)}^{2}}\] | |
| 10906. |
If a copper rod carries a direct current, the magnetic field associated with the current will be [CPMT 1984] |
| A. | Only inside the rod |
| B. | Only outside the rod |
| C. | Both inside and outside the rod |
| D. | Neither inside nor outside the rod |
| Answer» D. Neither inside nor outside the rod | |
| 10907. |
Electron volt is a unit of [MP PMT 2001] |
| A. | Potential |
| B. | Charge |
| C. | Power |
| D. | Energy |
| Answer» E. | |
| 10908. |
A sphere of mass m, moving with velocity V, enters a hanging bag of sand and stops. If the mass of the bag is M and it is raised by height h, then the velocity of the sphere was [MP PET 1997] |
| A. | \[\frac{M+m}{m}\sqrt{2gh}\] |
| B. | \[\frac{M}{m}\sqrt{2gh}\] |
| C. | \[\frac{m}{M+m}\sqrt{2gh}\] |
| D. | \[\frac{m}{M}\sqrt{2gh}\] |
| Answer» B. \[\frac{M}{m}\sqrt{2gh}\] | |
| 10909. |
Assertion : The change in air pressure effect the speed of sound. Reason : The speed of sound in a gas is proportional to square root of pressure. |
| 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. |
| Answer» E. | |
| 10910. |
Assertion : Two similar trains are moving along the equatorial line with the same speed but in opposite direction. They will exert equal pressure on the rails. Reason : In uniform circular motion the magnitude of acceleration remains constant but the direction continuously changes. |
| 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. |
| Answer» E. | |
| 10911. |
Assertion : The graph between velocity and displacement for a harmonic oscillator is a parabola. Reason : Velocity does not change uniformly with displacement in harmonic motion. |
| 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. |
| Answer» E. | |
| 10912. |
Assertion : We cannot produce a real image by plane or convex mirrors under any circumstances. Reason : The focal length of a convex mirror is always taken as positive. |
| 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. |
| Answer» E. | |
| 10913. |
The threshold wavelength for photoelectric emission from a material is 5200 Å. Photo-electrons will be emitted when this material is illuminated with monochromatic radiation from a [IIT JEE 1982; MP PMT 1992; MP PET 1999; UPSEAT 2001; KCET 2004; J & K CET 2004; BHU 2004] |
| A. | 50 watt infrared lamp |
| B. | 1 watt infrared lamp |
| C. | 50 watt ultraviolet lamp |
| D. | 1 watt ultraviolet lamp |
| Answer» E. | |
| 10914. |
Assertion : Lenz?s law violates the principle of conservation of energy. Reason : Induced e.m.f., opposes always the change in magnetic flux responsible for its production. |
| 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. |
| Answer» E. | |
| 10915. |
A force of 5 N acts on a 15 kg body initially at rest. The work done by the force during the first second of motion of the body is [JIPMER 1999] |
| A. | 5 J |
| B. | \[\frac{5}{6}J\] |
| C. | 6 J |
| D. | \[75\,J\] |
| Answer» C. 6 J | |
| 10916. |
A 50kg man with 20kg load on his head climbs up 20 steps of 0.25m height each. The work done in climbing is [JIPMER 2002] |
| A. | 5 J |
| B. | 350 J |
| C. | 100 J |
| D. | 3430 J |
| Answer» E. | |
| 10917. |
A force \[\overrightarrow{F}=(5\hat{i}+4\hat{j})\] N acts on a body and produces a displacement \[\overrightarrow{S}=(6\hat{i}-5\hat{j}+3\hat{k})\]m. The work done will be [CPMT 2003] |
| A. | 10 J |
| B. | 20 J |
| C. | 30 J |
| D. | 40 J |
| Answer» B. 20 J | |
| 10918. |
A particle is acted upon by a force of constant magnitude which is always perpendicular to the velocity of the particle, the motion of the particle takes place in a plane. It follows that [AIEEE 2004] |
| A. | Its velocity is constant |
| B. | Its acceleration is constant |
| C. | Its kinetic energy is constant |
| D. | It moves in a straight line |
| Answer» D. It moves in a straight line | |
| 10919. |
The kinetic energy acquired by a body of mass m is travelling some distance s, starting from rest under the actions of a constant force, is directly proportional to [Pb. PET 2000] |
| A. | \[{{m}^{0}}\] |
| B. | m |
| C. | \[{{m}^{2}}\] |
| D. | \[\sqrt{m}\] |
| Answer» B. m | |
| 10920. |
A spring of spring constant 5 ´ 103 N/m is stretched initially by 5cm from the unstretched position. Then the work required to stretch it further by another \[5cm\] is [AIEEE 2003] |
| A. | 6.25 N-m |
| B. | 12.50 N-m |
| C. | 18.75 N-m |
| D. | 25.00 N-m |
| Answer» D. 25.00 N-m | |
| 10921. |
The potential energy of a body is given by, U =\[A-B{{x}^{2}}\](Where x is the displacement). The magnitude of force acting on the particle is [BHU 2002] |
| A. | Constant |
| B. | Proportional to x |
| C. | Proportional to \[{{x}^{2}}\] |
| D. | Inversely proportional to x |
| Answer» C. Proportional to \[{{x}^{2}}\] | |
| 10922. |
An engine is hauling a train of mass M kg on a level track at a constant speed v m/s. The resistance due to friction is\[fN/kg\]. What extra power must the engine develop to maintain the speed up a gradient of h in s : |
| A. | \[\frac{mghv}{s}\] |
| B. | \[\frac{mghs}{v}\] |
| C. | \[Mghvs\] |
| D. | zero |
| Answer» B. \[\frac{mghs}{v}\] | |
| 10923. |
A block of mass \[m=1\text{ }kg\]is moving with a constant acceleration \[a=1\text{ }m/{{s}^{2}}\]on a rough horizontal plane. The coefficient of friction between the block and plane is\[u=0.1\]. The initial velocity of block is zero at\[t=0\]. The power delivered by the external agent at a time t = 2 sec from the beginning is equal to \[\left( Takeg= 10m/{{s}^{2}} \right)\] |
| A. | 1 watt |
| B. | 2 watt |
| C. | 3 watt |
| D. | 4 watt |
| Answer» E. | |
| 10924. |
A body of mass 1 kg begins to move under the action of a time dependent force\[\vec{F}=\left( 2t\hat{i}+3{{t}^{2}}\hat{j} \right]) N,\], where \[\hat{i} and \hat{j}\]are unit vectors alogn x and y axis. What power will be developed by the force at the time t? |
| A. | \[\left( 2{{t}^{2}}+3{{t}^{3}} \right)W\] |
| B. | \[\left( 2{{t}^{2}}+4{{t}^{4}} \right)W\] |
| C. | \[\left( 2{{t}^{3}}+3{{t}^{4}} \right)W\] |
| D. | \[\left( 2{{t}^{3}}+3{{t}^{5}} \right)W\] |
| Answer» E. | |
| 10925. |
A force applied by an engine of a train of mass \[2.05\times 1{{0}^{6}} kg\]changes its velocity from 5m/s to 25 m/s in 5 minutes. The power of the engine is |
| A. | 1.025 MW |
| B. | 2.05 MW |
| C. | 5 MW |
| D. | 6 MW |
| Answer» E. | |
| 10926. |
If two persons A and B take 2 seconds and 4 seconds respectively to lift an object to the same height h, then the ratio of their powers is |
| A. | 0.0430555555555556 |
| B. | 0.0423611111111111 |
| C. | 0.0840277777777778 |
| D. | 0.04375 |
| Answer» D. 0.04375 | |
| 10927. |
A body is moved along a straight line by a machine delivering a constant power. The distance moved by the body in time 'f' is proportional to |
| A. | \[{{t}^{3/4}}\] |
| B. | \[{{t}^{3/2}}\] |
| C. | \[{{t}^{1/4}}\] |
| D. | \[{{t}^{1/2}}\] |
| Answer» C. \[{{t}^{1/4}}\] | |
| 10928. |
A body of mass m is accelerated uniformly from rest to a speed v in a time T. The instantaneous power delivered to the body as a function of time is given by |
| A. | \[\frac{m{{v}^{2}}}{{{T}^{2}}}.{{t}^{2}}\] |
| B. | \[\frac{m{{v}^{2}}}{{{T}^{2}}}.t\] |
| C. | \[\frac{1}{2}\frac{m{{v}^{2}}}{{{T}^{2}}}.{{t}^{2}}\] |
| D. | \[\frac{1}{2}\frac{m{{v}^{2}}}{{{T}^{2}}}.t\] |
| Answer» C. \[\frac{1}{2}\frac{m{{v}^{2}}}{{{T}^{2}}}.{{t}^{2}}\] | |
| 10929. |
Two blocks of masses m and M are joined with an ideal spring of spring constant k and kept on a rough surface as shown. The spring is initially unstretched and the coefficient of friction between the blocks and the horizontal surface is u. What should be the maximum speed of the block of mass M such that the smaller block does not move? |
| A. | \[\mu g\sqrt{\frac{Mm}{\left( M+m \right)k}}\] |
| B. | \[\mu g\sqrt{\frac{\left( M+m \right)k}{Mm}}\] |
| C. | \[\mu g\sqrt{\frac{\left( 2M+m \right)m}{kM}}\] |
| D. | None of these |
| Answer» D. None of these | |
| 10930. |
A force F acting on an object varies with distance x as shown here. The force is in N and x in m. The work done by the force in moving the object from \[x=0\] to \[x=6\] m is |
| A. | 18.0 J |
| B. | 13.5 J |
| C. | 9.0 J |
| D. | 4.5 J |
| Answer» C. 9.0 J | |
| 10931. |
A man places a chain of mass m and length L on a table slowly. Initially the lower end of the chain just touches the table. The man drops the chain when half of the chain is in vertical position. Then work done by the man in this process is |
| A. | \[-mg\frac{L}{2}\] |
| B. | \[-\frac{mg\,L}{4}\] |
| C. | \[-\frac{3mg\,L}{8}\] |
| D. | \[-\frac{mg\,L}{8}\] |
| Answer» D. \[-\frac{mg\,L}{8}\] | |
| 10932. |
A body falls freely under gravity. Its velocity is v when it has lost potential energy equal to U. What is the mass of the body? |
| A. | \[{{\operatorname{U}}^{2}}/{{v}^{2}}\] |
| B. | \[2{{\operatorname{U}}^{2}}/{{v}^{2}}\] |
| C. | \[2\operatorname{U}/{{v}^{2}}\] |
| D. | \[\operatorname{U}/{{v}^{2}}\] |
| Answer» D. \[\operatorname{U}/{{v}^{2}}\] | |
| 10933. |
One man takes 1 min. to raise a box to a height of 1 metre and another man takes 1/2 min. to do so. The energy of the |
| A. | Two is different |
| B. | two is same |
| C. | first is more |
| D. | second is more |
| Answer» C. first is more | |
| 10934. |
Four particles given, have same momentum. Which has maximum kinetic energy |
| A. | Proton |
| B. | Electron |
| C. | Deutron |
| D. | a-particles |
| Answer» C. Deutron | |
| 10935. |
A man starts walking from a point on the surface of earth (assumed smooth) and reaches diagonally opposite point. What is the work done by him? |
| A. | Zero |
| B. | Positive |
| C. | Negative |
| D. | Nothing can be said |
| Answer» B. Positive | |
| 10936. |
A block of mass \[m=0.1\] kg is connected to a spring of unknown spring constant k. It is compressed to a distance \[\left( \frac{x}{2} \right)\] from its equilibrium position and released from rest. After approaching half the distance from equilibrium position, it hits another block and comes to rest momentarily, while the other block moves with a velocity\[3m{{s}^{-1}}\]. The total initial energy of the spring is |
| A. | \[0.3\text{ }J\] |
| B. | \[0.6\text{ }J\] |
| C. | \[0.8\text{ }J\] |
| D. | \[1.5\text{ }J\] |
| Answer» C. \[0.8\text{ }J\] | |
| 10937. |
Two bodies of masses 4 kg and 5 kg are moving with equal momentum. Then the ratio of their respective kinetic energies is |
| A. | \[4:5\] |
| B. | \[2:1\] |
| C. | \[1:3\] |
| D. | \[5:4\] |
| Answer» E. | |
| 10938. |
At time \[t=0s\] particle starts moving along the x-axis. If its kinetic energy increases uniformly with time f, the net force acting on it must be proportional to |
| A. | \[\sqrt{t}\] |
| B. | constant |
| C. | \[t\] |
| D. | \[\frac{1}{\sqrt{t}}\] |
| Answer» E. | |
| 10939. |
The work done by a force\[\vec{F}=\left( -6{{x}^{3}}\hat{i} \right)N,\]in displacing a particle from \[x=4\text{ }m\text{ }to\text{ }x=-2\]m is |
| A. | \[360J\] |
| B. | \[240J\] |
| C. | \[-240J\] |
| D. | \[-360J\] |
| Answer» B. \[240J\] | |
| 10940. |
A ball whose kinetic energy is E, is projected at an angle of \[45{}^\circ \] to the horizontal. The kinetic energy of the ball at the highest point of its flight will be |
| A. | E |
| B. | \[E/\sqrt{2}\] |
| C. | \[E/2\] |
| D. | zero |
| Answer» D. zero | |
| 10941. |
A man is riding on a cycle with velocity 7.2 km/hr up a hill having a slope 1 in 20. The total mass of the man and cycle is 100 kg. The power of the man is |
| A. | 200 W |
| B. | 175 W |
| C. | 125 W |
| D. | 98 W |
| Answer» E. | |
| 10942. |
An engine pump is used to pump a liquid of density \[\rho \] continuously through a pipe of cross-sectional area A. If the speed of flow of the liquid in the pipe is v, then the rate at which kinetic energy is being imparted to the liquid is |
| A. | \[\frac{1}{2}A\rho {{v}^{3}}\] |
| B. | \[\frac{1}{2}A\rho {{v}^{2}}\] |
| C. | \[\frac{1}{2}A\rho v\] |
| D. | \[A\rho v\] |
| Answer» B. \[\frac{1}{2}A\rho {{v}^{2}}\] | |
| 10943. |
A quarter horse power motor runs at a speed of 600 r.p.m. Assuming 40% efficiency the work done by the motor in one rotation will be [Kerala PET 2002] |
| A. | 7.46 J |
| B. | 7400 J |
| C. | 7.46 ergs |
| D. | 74.6 J |
| Answer» B. 7400 J | |
| 10944. |
A 60 kg man runs up a staircase in 12 seconds while a 50 kg man runs up the same staircase in 11, seconds, the ratio of the rate of doing their work is [AMU (Engg.) 2001] |
| A. | 6 : 5 |
| B. | 12 : 11 |
| C. | 11 : 10 |
| D. | 10 : 11 |
| Answer» D. 10 : 11 | |
| 10945. |
The power of a pump, which can pump 200kg of water to a height of 200m in 10sec is \[(g=10m/{{s}^{2}})\] [CBSE PMT 2000] |
| A. | 40 kW |
| B. | 80 kW |
| C. | 400 kW |
| D. | 960 kW |
| Answer» B. 80 kW | |
| 10946. |
A body of mass m moving with a constant velocity v hits another body of the same mass moving with the same velocity v but in the opposite direction and sticks to it. The velocity of the compound body after collision is [NCERT 1977; RPMT 1999] |
| A. | v |
| B. | 2v |
| C. | Zero |
| D. | v/2 |
| Answer» D. v/2 | |
| 10947. |
A bullet of mass a and velocity b is fired into a large block of mass c. The final velocity of the system is [AFMC 1981, 94, 2000; NCERT 1971; MNR 1998] |
| A. | \[\frac{c}{a+b}\cdot b\] |
| B. | \[\frac{a}{a+c}\cdot b\] |
| C. | \[\frac{a+b}{c}.a\] |
| D. | \[\frac{a+c}{a}\cdot b\] |
| Answer» C. \[\frac{a+b}{c}.a\] | |
| 10948. |
A body of mass \[{{m}_{1}}\]is moving with a velocity V. It collides with another stationary body of mass \[{{m}_{2}}.\] They get embedded. At the point of collision, the velocity of the system [DCE 1999, 2001] |
| A. | Increases |
| B. | Decreases but does not become zero |
| C. | Remains same |
| D. | Become zero |
| Answer» C. Remains same | |
| 10949. |
Which of the following is not a perfectly inelastic collision [BHU 1998; JIPMER 2001, 02; BHU 2005] |
| A. | Striking of two glass balls |
| B. | A bullet striking a bag of sand |
| C. | An electron captured by a proton |
| D. | A man jumping onto a moving cart |
| Answer» B. A bullet striking a bag of sand | |
| 10950. |
A heavy particle hanging from a string of length \[l\]is projected horizontally with speed \[\sqrt{2gl}\]. The speed of the particle at the point where the tension in the string equals weight of the particle |
| A. | \[\sqrt{2gl}\] |
| B. | \[\sqrt{3gl}\] |
| C. | \[\sqrt{gl/2}\] |
| D. | \[\sqrt{gl/3}\] |
| Answer» E. | |