NEET Physics Angular Displacement Velocity and Acceleration MCQs Set A

a)

b)

c)

d) None of these

Answer:

Question: Concrete mixture is made by mixing cement, stone and sand in a rotating cylindrical drum. If the drum rotates too fast, the ingredients remain stuck to the wall of the drum and proper mixing of ingredients does not take place. The maximum rotational speed of the drum in revolutions per minute (rpm) to ensure proper mixing is close to : (Take the radius of the drum to be 1.25 m and its axle to be horizontal):

a) 27.0

b) 0.4

c) 1.3

d) 8.0

Answer: 27.0

Question: A rod PQ of mass M and length L is hinged at end P. The rod is kept horizontal by a massless string tied to point Q as shown in figure. When string is cut, the initial angular acceleration of the rod is

a)

b)

c) 2g/L

d) g /L

Answer:

Question: Angular velocity of each particle of a rotating rigid body about axis of rotation is

a) same

b) different

c) depends on relative position

d) None of these

Answer: same

Question: A wheel rotates with a constant acceleration of 2.0 radian/sec². If the wheel starts from rest, the number of revolutions it makes in the first ten seconds will be approximately

a) 16

b) 8

c) 24

d) 32

Answer: 16

Question: The wheel of a car is rotating at the rate of 1200 revolutions per minute. On pressing the accelerator for 10 seconds. It starts rotating at 4500 revolutions per minute. The angular acceleration of the wheel is

a) 1980 degree/second²

b) 1880 degree/second²

c) 30 radians/second²

d) 40 radians/second²

Answer: 1980 degree/second²

Question: A wheel has a speed of 1200 revolutions per minute and is made to slow down at a rate of 4 radians/s2. The number of revolutions it makes before coming to rest is

a) 314

b) 722

c) 272

d) 143

Answer: 314

Question: When a ceiling fan is switched off, its angular velocity falls to half while it makes 36 rotations. How many more rotations will it make before coming to rest?

a) 12

b) 18

c) 36

d) 24

Answer: 12

Question: A mass is revolving in a circle which is in the plane of paper. The direction of angular acceleration is

a) upward the radius

b) towards the radius

c) tangential

d) at right angle to angular velocity

Answer: upward the radius

Question: A wheel is rotating at 1800 rpm about its own axis. When the power is switched off, it comes to rest in 2 minutes. Then the angular retardation in rad s^–1 is

a)

b)

c)

d)

Answer: