What are the contact forces? Describe two forces that are contact forces.
The force acting on objects, when two objects come in contact with each other are known as contact forces.
Examples of contact forces are given below:
1. Muscular Force: Force exerted due to the action of muscles. This force is categorised as contact force because, it comes in play only when an object is being handled.
Example: bending, running, moving etc.
2. Friction: Force exerted on an object when its surface comes in contact with another surface. This force comes into action only when the two surfaces come in contact with each other and hence are called contact forces.
How can you demonstrate the presence of atmospheric pressure experimentally? Illustrate with a diagram.
Describe an activity to observe the relation of pressure and surface area of an object.
What are the changes caused due to force applied on an object?
An inflated gas balloon is placed in a sealed jar which is connected to an evacuating pump. What will be observed if the air inside the jar is pumped out? Give a reason justifying your answer.
