Class 7 (Science Assignment)

 

Simple Machines

Simple machines are tools that help us do work more easily. They reduce the effort needed to perform a task by changing the size or direction of a force. Simple machines do not reduce the amount of work done, but they make work easier and more convenient.

There are six basic types of simple machines: lever, pulley, wheel and axle, inclined plane, screw, and wedge. A lever is a rigid bar that turns around a fixed point called a fulcrum. A seesaw, scissors, and a crowbar are examples of levers. A pulley is a wheel with a groove that holds a rope. It helps lift heavy objects by changing the direction of force.

An inclined plane is a sloping surface that helps move objects from a lower level to a higher level with less effort. A ramp is a common example of an inclined plane. A wedge is a simple machine with a sharp edge used for cutting or splitting objects, such as a knife or axe. A screw is an inclined plane wrapped around a cylinder and is used to hold things together.

Simple machines are used in our daily lives. They are found in machines, vehicles, construction tools, and household items. Understanding simple machines helps us design better tools and solve practical problems.

Questions

1. What is the main purpose of simple machines?

2. Name the six basic types of simple machines.

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

4. How does a pulley help us lift heavy objects?

5. Why is a ramp considered an inclined plane?

6. Give two examples of simple machines used in your daily life and explain how they help you.