Question

1. Define centre of mass of a body . [1]
2. Write expression for conservation of momentum in terms of centre
of mass? [2]
3. Is centre of mass always a reality ? [1]
4. What do you mean by rigid body? [1]
5. What is the relationship between escape velocity and orbital
velocity . [2]
6. Give an example where centre of mass lies inside the body and
outside the body [2]
7. Obtain the relation between torque ,and moment of inertia [2]
8. Write newton’s law of graviation . [1]
9. What do you mean by escape velocity ? [1]
PART – 02 [each question carries – 3 marks]
10.Prove on moving above the earth surface value of g decreases ? [3]
11.Obtain expression for rotational kinetic energy ? [3]
12. The moment of ineria of a fly wheel is 4 kg /m2 . what angular accelration will be produced in it by applying a torque of 10 Nm. on it. [3]
13. What do you mean by gravitational potential , obtain expression for it .[3]

Answer 1

In physics, the center of mass of a distribution of mass in space is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may be applied to cause a linear acceleration without an angular acceleration.