1.  Function of ball bearing in a wheel is -

Answer & Explanation
to convert kinetic friction into rolling friction

2.  Rocket acts on Law of conservation of-

Answer & Explanation
Liner Momentum

3.  Weight of a free falling body is -

Answer & Explanation
Zero

4.  Water drop cannot stick to the oily surface due to

Answer & Explanation
lack of adhesive force

5.  Why the rain drops acquired the spherical shape?

Answer & Explanation
Surface tension

6.  A fountain pen works on the principle of-

Answer & Explanation
Capilarism

7.  The part of transistor which is heavily doped to produce a large number of majority carriers is -

Answer & Explanation
Emitter

8.  Time period of Revolution for a Geo-stationary satellite is-

Answer & Explanation
24 Hours

9.  What is the Height of a Geo-Stationary satellite from the surface of earth?

Answer & Explanation
36,000 km (nearly)

10.  Rice is cooked more quickly in a pressure cooker because -

Answer & Explanation
water boils at Higher temperature.

11.  For a missile Launched with A velocity Less than the escape velocity of earth, the total energy is

Answer & Explanation
Negative

12.  Cooking of Rice is Harder -

Answer & Explanation
Top of Mountains

13.  What is the working principle of Rocket?

Answer & Explanation
Newton's 3rd Law

14.  What should a person on a freely rotating turn able to decrease his angular speed?

Answer & Explanation
Spread his hand outward

15.  Energy stored in a spring in watch -

Answer & Explanation
Potential Energy