ROTATIONAL MOTION

In which direction do the torques act when two equal parallel forces act in the same direction at the ends of a rod?

• Same direction
• Perpendicular to each other
• Random directions
• Opposite to each other

What determines the magnitude of torque in a couple?

• The sum of the two forces
• The average of the two forces
• The product of both forces
• The product of one force and the perpendicular distance between the two forces

What is the torque produced by a couple on a rod of length 2a with forces F at each end?

• aF
• aF/2
• 0
• 2aF

What is the rotational effect when two equal and opposite forces act along the same line?

• Pure rotation occurs
• The body translates
• No rotation occurs
• The body vibrates

Why is the net force zero in the case of a couple?

• Because the forces are perpendicular to the body
• Because one force is larger than the other
• Because they act at the same point
• Because the two forces are equal in magnitude and opposite in direction