## Wednesday 24 July 2013

### CBSE Class IX (9th) Science | Chapter 10. GRAVITATION | Solved Exercises

Question 1.How does the force of gravitation between two objects change when the distance between them is reduced to half

Answer. According to the law of gravitation , the force of attraction between any two objects of mass m1 and m2 is proportional to the product of their masses and inversely proportional to the square of the distance 'R' between them.
 As given here F = Gm1 × m2 R²

## Saturday 6 July 2013

### CBSE Class IX (9th) Science | Chapter 9. FORCE AND LAWS OF MOTION | Solved Exercises

Question 1. An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.

Answer : Yes, it possible for an object to be traveling with a non-zero velocity, if the object experiences a net zero external unbalanced force.