Multiple Choice Questions (MCQ) with Answers on Physics – Set 1
17-The viscous force acting on a solid ball moving in air with terminal velocity v is directly proportional to
- √v
- v
- 1/√v
- v2
(Ans: b)
18- A particle of mass ‘m0’ moves with speed 0.8c, where ‘c’ is the speed of light in vacuum. The relativistic kinetic energy of the particle is nearly
- 1.66m0c2
- m0c2
- 0.32m0c2
- 0.66 m0c2
(Ans: d)
19-In a uniform circular motion
- Velocity and acceleration both are constant
- Acceleration and speed are constant but velocity changes
- Acceleration and velocity both change
- Acceleration and speed both are constant
(Ans: c)
20-A motor cyclist moving with a velocity of 72km/hr on a flat road takes a turn at a point where the radius of curvature of the rod is 20m(g=10m/s2).In order to avoid sliding, he must not bend with respect to the vertical by an angle 0 greater than
- tan-1 2
- tan-1 4
- tan-1 6
- tan-1 25.92
(Ans: b)
21-A particle of mass 0.5 kg is moving in a circle of radius 0.1 m with a constant speed of 2.0m/s. Its acceleration at any moment is
- zero
- 10 m/s2
- 25 m/s2
- 40 m/s2
(Ans: d)
22-lf the kinetic energy of a body becomes four times its initial value, the new momentum will be
- Three times the initial value
- Four times the initial value
- Two times the initial value
- unchanged
(Ans: c)
23-A ship of mass 3x 10^7 kg initially at rest, can be pulled through a distance of 3m by means of force 5x 10^4 N. The water resistance is negligible. The speed attained by the ship is
- 0.1m/s
- 0.5m/s
- 1.0m/s
- 5.0m/s
(Ans: a)
24-If the radius of the earth were to shrink, its mass remaining the same, the value of acceleration due to gravity at the pole and at the equator will
- Increase and decrease respectively
- Decrease and increase respectively
- Increase at both places
- Decrease at both places
(Ans: c)
25-Lorentz transformation equations hold for
- Non-relativistic velocities only
- Relativistic velocities only
- All velocities: relativistic & non-relativistic
- Photons only
(Ans: c)
26-A particle is dropped from a point above the earth. The ratio of the distance travelled in the first two seconds and in the next two seconds is
- 1:1
- 1:2
- 1:3
- 1:4
(Ans: c)
27-A mass ‘M’ when attached to the lower end of a mass less spring, whose upper end is fixed, extends it by ‘L’. In the extended equilibrium state of the spring, the restoring force exerted by the spring on the mass is
- Mg
- Mg/2
- 2/Mg
- Zero
(Ans: a)
28-Under the influence of a transverse magnetic field, an electron moves in a circle with constant speed ‘v’. The time period of revolution is
- Proportional to v
- Proportional to v2
- Proportional to √v
- Independent of v
(Ans: d)
29-The maximum velocity of a particle, executing simple harmonic motion with amplitude 7 mm, is 4.4 m/s. The period of oscillation is
- 100.00 s
- 10.00 s
- 0.10 s
- 0.01 s
(Ans: d)
30-The equation, x = a cos (ωt + f) represents
- Acceleration due to gravity
- Uniform straight line motion
- dc current
- Simple harmonic motion
(Ans: d)
31-Relative to its period on the earth, the period a pendulum on the moon is
- Shorter
- Longer
- The same as on the earth
- Varies with time
(Ans: b)
32-The phenomenon that cannot take place in sound waves is
- reflection
- interference
- diffraction
- polarization
(Ans: d)