ROTATIONAL MOTION

What happens to the centre of gravity when a body is taken to the moon?

• It moves to the centre
• It disappears
• It remains the same relative to the body
• It becomes heavier

How does the principle of moments apply to the balanced cardboard?

• It applies only to liquids
• It requires no forces
• The sum of clockwise moments equals sum of counterclockwise moments
• It doubles the weight

What is the effect of the pencil's material on balancing the cardboard?

• It changes the CG
• It alters gravity
• Minimal, as long as it provides sufficient reaction force
• It makes the experiment invalid

Why can't a body rotate when net torque is zero?

• Because it is too heavy
• Because friction stops it
• Because there is no angular acceleration
• Because gravity vanishes

What is the significance of the vector sum Σ rᵢ × mᵢg = 0?

• It measures speed
• It calculates temperature
• It defines the location of the centre of gravity
• It shows the object is moving