Question

A particle undergoes uniform circular motion. About which point in the plane of the circle, will the angular momentum of the particle remain conserved?
A. Centre of the circle
B. On the circumference of circle
C. Inside the circle other than centre
D. Outside the circle

Answer 1

Hint: The only force acting on the particle in uniform circular motion is centripetal ( towards centre). This force's torque around the centre is zero. And at the other point of the circle, either it is inside or outside of the circle, it is not constant.

Complete answer:
The particle's face passes through the centre of the circle in uniform circular motion, its torque about its point is zero, and angular momentum is conserved.Or, in other words, a constant speed is achieved when an object moves in a uniform circular motion. Despite this, it is speeding up as a result of its new orientation.... However, because the inward net force is oriented perpendicular to the velocity vector, the object is constantly changing direction and accelerating inward.

The rotational analogue of linear momentum is angular momentum (rarely, moment of momentum or rotational momentum). Because it is a conserved quantity—the total angular momentum of a closed system remains constant—it is a significant quantity in physics. The moment of inertia times the angular velocity equals angular momentum. Because its moment of inertia grows, the rotational speed must decrease to maintain angular momentum.

Hence, the correct option is A.

Note: There are multiple parameters that remain constant in a uniform circular motion. Any given quantity becomes variable rather than constant when the direction of vector quantities changes. The centripetal force is determined by the mass of the item, its speed, rotation frequency, and the radius of the circular route along which it moves.