Question

Answer the question:
​

Answer 1

4. A pulley is a wheel or axle or shaft that is designed to support movement and change of direction of a taut cable or belt or transfer of power between the shaft and cable of belt.

Types:

Fixed pulley

Movable pulley

Compound pulley

Answer 2

Answer:

Ans.1: Simple machines that are widely used include the wheel and axle, pulley, inclined plane, screw, wedge and lever. While simple machines may magnify or reduce the forces that can be applied to them, they do not change the total amount of work needed to perform the overall task.

Ans.2: A lever is a bar or board that rests on a support called a fulcrum. A downward force exerted on one end of the lever can be transferred and increased in an upward direction at the other end, allowing a small force to lift a heavy weight.All early people used the lever in some form, for example, for moving heavy stones or as digging sticks for land cultivation.

Ans.3: A wheel and axle is made up of a circular frame (the wheel) that revolves on a shaft or rod (the axle). In its earliest form it was probably used for raising weights or water buckets from wells.

Ans.4: A pulley is a wheel that carries a flexible rope, cord, cable, chain, or belt on its rim. Pulleys are used singly or in combination to transmit energy and motion. Pulleys with grooved rims are called sheaves. In belt drive, pulleys are affixed to shafts at their axes, and power is transmitted between the shafts by means of endless belts running over the pulleys.

Ans.5: Because there is load effort and fulcrum, it works as a lever. When it is in use the load and effort can vary continuously for 360° on the circumference of the wheel and axle. Hence it is a continuous lever.

Ans.6: Similarities Between The Inclined Plane And Wedge

Both the wedge and inclined plane: include an inclined plain. make work easier by requring less force. ... The wedge splits an object and the plane splits the force of gravity.

Ans.7: A screw is a usually circular cylindrical member with a continuous helical rib, used either as a fastener or as a force and motion modifier.

Ans.8: Simple machines are useful because they reduce effort or extend the ability of people to perform tasks beyond their normal capabilities.