Find out any five activities in your surroundings or daily routine that use revolute joints. Discuss their functioning in detail.

A revolute joint is a type of joint that allows rotational movement around a fixed axis. In such joints, one part rotates relative to another, similar to the motion of a hinge. The following activities from daily life use revolute joints:

1. Opening and closing a door
   A door rotates about its hinges fixed to the door frame. The hinge acts as a revolute joint, allowing the door to rotate in one direction around a fixed axis.
2. Turning a steering wheel of a vehicle
   The steering wheel rotates around a central axis. This rotational movement helps control the direction of the vehicle and is an example of a revolute joint.
3. Movement of the elbow joint in the human arm
   The elbow allows the forearm to rotate around a fixed point relative to the upper arm. This hinge-like movement is similar to a revolute joint and enables bending and straightening of the arm.
4. Pedals of a bicycle
   Bicycle pedals rotate about their central axle. This rotational motion helps convert the rider’s force into movement, demonstrating the working of a revolute joint.
5. Rotation of a ceiling fan
   The blades of a ceiling fan rotate around a fixed central axis. This continuous rotational motion is an example of a revolute joint in operation.