8.
Answer the following questions in brief.
a. A plastic cube is released in water. Will
it sink or come to the surface of water?
3. Why do the load carrying heavy
vehicles have large number of wheels?
How much pressure do we carry on
our heads? Why don't we feel it?
Answers
Answer:
a . come on the water surface.
b. due to differences in capacity of pressure.
Answer the following questions in brief .
1. plastic cube is released in water. Will it sink or come to the surface of water?
Ans - If a plastic cube is put inside water it won't sink instead it will float on the surface of the water . The power of object to float on the surface of water is known as buoyancy, if the rate of buoyancy is high it will float. Plastic has a higher rate of buoyancy and is light and therefore it would float on the surface of the water,
2. Why do the load carrying heavy vehicles have large number of wheels?
Ans - we know that pressure = force/area.
so when the area of contact between two surfaces is greater , the pressure will be less. so the load carrying heavy vehicles have a large number of wheels so that the pressure on the road would be less due to larger contact area.
3. How much pressure do we carry on our heads? Why don't we feel it?
Ans - we carry about 10⁵ pa atmospheric pressure on our head. we can't feel this pressure because atmospheric pressure is balanced by the pressure that is made by the air and our blood inside our body.