Embibe Experts Solutions for Chapter: Circular Motion, Exercise 6: Exercise (Assertion & Reason)

Assertion : When a particle moves in a circle with a uniform speed its acceleration is constant but the velocity changes.
Reason : Angular displacement is not an axial vector.

Assertion : If a particle moves along circular path with constant speed then acceleration must be present.
Reason : If a particle moves with variable velocity then acceleration must be present.

Assertion: In uniform circular motion speed of particles must be constant.

Reason: In uniform circular motion no force or acceleration is acting on particle acting parallel or in antiparallel to the direction of velocity.

Assertion: When the direction of motion of a particle moving in a circular path is reversed the direction of radial acceleration still remains the same (at the given point).

Reason: For a particle revolving on a circular path in any direction such as clockwise or anticlockwise, the direction of radial acceleration is always towards the centre of the circular path.

Assertion: For uniform circular motion it is necessary that the speed of the particle is constant.

Reason: There is no tangential force or tangential acceleration acting on particles in a uniform circular motion.

Assertion: Acceleration of the particle in uniform circular motion remains constant.

Reason: The velocity of the particle doesn’t change in a circular motion.

Assertion: During a turn, the value of centripetal force should be less than the limiting frictional force.
Reason: The centripetal force is provided by the frictional force between the tyres and the road.

Assertion: When a car turns around a circular path it is acted upon by a centripetal force.

Reason: The friction acting on the wheels of the car provides the necessary centripetal force.