Belt drives transfer power using ________ created between the belt and the pulleys.

Belt drives transfer power using ________ created between the belt and the pulleys.

• A. Friction
• B. Tension
• C. Elasticity
• D. Heat

Answer: (A)

Power is transmitted in belt drives by the frictional grip between the belt and the pulley surfaces. When the belt is held tight, it presses against the pulley, creating a normal force that allows friction to act at the contact area. The friction force, which depends on the coefficient of friction and the normal force (F = μN), provides the driving torque that turns the pulley. The tighter the belt, the larger the normal force and thus the more torque can be transmitted before slipping occurs. Heat can be produced if slipping happens, but it’s a byproduct, not how the power is transferred. Elasticity and tension help maintain grip, but the actual transfer of power comes from friction.

Power is transmitted in belt drives by the frictional grip between the belt and the pulley surfaces. When the belt is held tight, it presses against the pulley, creating a normal force that allows friction to act at the contact area. The friction force, which depends on the coefficient of friction and the normal force (F = μN), provides the driving torque that turns the pulley. The tighter the belt, the larger the normal force and thus the more torque can be transmitted before slipping occurs. Heat can be produced if slipping happens, but it’s a byproduct, not how the power is transferred. Elasticity and tension help maintain grip, but the actual transfer of power comes from friction.