ROTATIONAL MOTION

What is the effect of a frictional torque on a rotating body?

• It increases speed
• It does no work
• It does negative work and reduces kinetic energy
• It changes the axis

What is the implication of dW = τdθ for energy conservation?

• It violates conservation
• It makes energy infinite
• It allows calculation of kinetic energy change from torque and angle
• It eliminates mass

What is the condition for a force to produce maximum angular acceleration?

• When force is radial
• When force is small
• When it produces maximum torque
• When time is short

What is the role of the z-axis in the rotational motion described?

• It is the direction of force
• It lies in the plane
• It is the fixed axis of rotation perpendicular to the plane of motion
• It is arbitrary

What is the significance of the cross product in τ = r × F?

• It calculates linear force
• It gives scalar work
• It ensures only the perpendicular component of force contributes to torque
• It measures energy