Question

One or more forces are acting in the following examples. Name them.
(a) An object falling from a tall building ….
(b) An aeroplane flying in sky ….
(c) Squeezing sugarcane juice with a squeezer ….…. .
(d) Winnowing foodgrain ……. .

Answer 1

1. The force acting upon an object falling from a tall building is gravitational force applied by the earth.

2. The forces acting upon aeroplane flying in the sky are lift, thrust, drag and weight.

3. The force acting while squeezing sugarcane juice with a squeezer is mechanical force applied by the squeezer.

4. The forces acting while winnowing food grain are muscular and gravitational forces applied by the body muscles and earth respectively. 

Answer 2

A. Gravitation force

B. Electrostatic force

C. Electrostatic force

D. Muscular force