Chap#05 Circular Motion

Question 1

A body moving in circular motion with constant speed has:

Answer 1

Constant kinetic energy

Question 2

Angular momentum is:

Answer 2

Vector (axial)

Question 3

What remains constant in the field of central force?

Answer 3

Angular Momentum

Question 4

What remains constant when the earth revolves around the sun?

Answer 4

Angular Momentum

Question 5

If the earth were to rotate faster, than its present speed the weight of an object will:

Answer 5

Decrease at the equator but remain unchanged at the poles

Question 6

The Centre of mass is a point:

Answer 6

Where the whole mass of the body is supposed to be centered

Question 7

A couple produces:

Answer 7

Purely rotational motion

Question 8

In which case application of angular velocity is useful?

Answer 8

When a body is rotating

Question 9

What will be the duration of the day and night (in hours) if the diameter of the earth is suddenly reduced to half its original value, the mass remaining constant

Answer 9

6

Question 10

A person standing on a rotating platform has his hands lowered. He suddenly outstretches his arms. The angular momentum:

Answer 10

Remains the same
➡When the hands are outstretched, a moment of inertia increases and angular velocity decreases. So, angular momentum remains unchanged.