Question

When you keep a book on a table the book doesn’t just fall through the

table. What makes it stay balanced on the table?

ii) Calculate the pressure produced in the following cases :

(a) Force = 800 N, Area = 8 m2

(b) Force = 10 N, Area = 5 m2​

Answer 1

1) Question :-

★ When you keep a book on a table the book doesn’t just fall through the table. What makes it stay balanced on the table?

→ The book which is lying on the table is exerting a downward force on the table. While the table is also exerting a upward force on opposite direction. Because the forces are equal to each other and opposite that's why book remain at rest.

→ Here the gravity force acting on the book. Basically the gravity force tries to accelerate the book towards the centre of earth. And the second force is the force that the table act on the book in the upward direction to stop it from accelerating.

2) Question :-

★ Calculate the pressure produced in the following cases :

(a) Force = 800 N, Area = 8 m2

We know that :-

→ P = F/A

Putting given values :-

→ P = 800 N/8 m^2

→ P = 100 N/m^2

(b) Force = 10 N, Area = 5 m2

We know that :-

→ P = F/A

Putting given values :-

→ P = 10 N/5 m^2

→ P = 2 N/m^2

Final answers :-

1) P = 100 N/m^2

2) P = 2 N/m^2