Which of the following is a simple machine?

Which of the following is a simple machine?

• A. Computer
• B. Lever
• C. Bridge
• D. Refrigerator

Answer: (B)

Simple machines help us do work more easily by changing the size or direction of a force. A lever is a simple machine made from a rigid bar with a pivot point, called a fulcrum. If you apply force on one end, the bar rotates around the fulcrum and can lift a load on the other end. The distance from the fulcrum to where you push and to where the load sits determines how much effort you need; a longer effort arm means you can lift heavier loads with less force, giving you mechanical advantage. The other options aren’t simple machines by themselves: a computer is a complex device built from many parts, a bridge is a structure designed to carry loads, and a refrigerator contains several components and mechanisms working together.

Simple machines help us do work more easily by changing the size or direction of a force. A lever is a simple machine made from a rigid bar with a pivot point, called a fulcrum. If you apply force on one end, the bar rotates around the fulcrum and can lift a load on the other end. The distance from the fulcrum to where you push and to where the load sits determines how much effort you need; a longer effort arm means you can lift heavier loads with less force, giving you mechanical advantage. The other options aren’t simple machines by themselves: a computer is a complex device built from many parts, a bridge is a structure designed to carry loads, and a refrigerator contains several components and mechanisms working together.