Class 7 (Science Assignment)

 

Passage

A simple machine is a tool that makes work easier by changing the size or direction of a force. Simple machines help us lift, move, or cut objects with less effort. There are six types of simple machines: lever, pulley, wheel and axle, inclined plane, wedge, and screw.

A lever consists of a rigid bar that rotates around a fixed point called a fulcrum. Examples of levers include a seesaw, crowbar, and bottle opener. A pulley uses a wheel and a rope to lift heavy loads. Cranes and flagpoles use pulleys. A wheel and axle help move objects more easily, such as in bicycles and doorknobs.

An inclined plane is a sloping surface used to raise or lower objects with less effort. Ramps are examples of inclined planes. A wedge is used for cutting or splitting materials; knives and axes are wedges. A screw is an inclined plane wrapped around a cylinder and is used to hold objects together or lift materials.

Simple machines are commonly used in homes, schools, industries, and construction sites. They help save time and energy and make many tasks safer and more efficient.

Questions

1.     What is a simple machine?

2.     Name the six types of simple machines.

3.     What is the fixed point around which a lever rotates called?

4.     Give two examples of a wedge.

5.     How do simple machines make work easier?