What term describes a bar free to pivot about a fixed point?

What term describes a bar free to pivot about a fixed point?

• A. Wheel and Axle
• B. Inclined Plane
• C. Lever
• D. Pulley

Answer: (C)

A lever is a rigid bar that pivots about a fixed point called the fulcrum. This description—bar free to rotate around a fixed point—fits exactly what’s described here. When you apply force on one end, the bar rotates around the fulcrum and can lift or move a load on the other end, with the distances from the fulcrum affecting how much effort is needed. That’s what makes this term the best fit. The other options describe different simple machines: a wheel and axle, which involves a wheel connected to an axle; an inclined plane, a sloped surface used to raise objects with less effort; and a pulley, a wheel with a rope to change the direction of a force.

A lever is a rigid bar that pivots about a fixed point called the fulcrum. This description—bar free to rotate around a fixed point—fits exactly what’s described here. When you apply force on one end, the bar rotates around the fulcrum and can lift or move a load on the other end, with the distances from the fulcrum affecting how much effort is needed. That’s what makes this term the best fit. The other options describe different simple machines: a wheel and axle, which involves a wheel connected to an axle; an inclined plane, a sloped surface used to raise objects with less effort; and a pulley, a wheel with a rope to change the direction of a force.