9th Class Physics Chapter 4 Test4. Dynamics-II

Q1. Multiple choice questions (Attempt all · 10 × 1 = 10)

1. The centre of gravity of a regular shaped body is always on its centre of:
   1. Body
   2. Symmetry
   3. Medians
   4. Axis
2. In circular motion, the motion of every particle of body is:
   1. Different
   2. Opposite
   3. Same
   4. None of these
3. The torque of a rotating fan is:
   1. Positive
   2. Negative
   3. Zero
   4. Scalar
4. It is more difficult to walk on a slippery surface than on a nonslippery one because of.
   1. Reduced friction
   2. Increased friction
   3. High grip
   4. Lower weight
5. Moon completes its revolution around the Earth in:
   1. 30 days
   2. 27.3 daya
   3. 31 days
   4. 365 days
6. First condition of equilibrium is represented by:
   1. ΣF = 0
   2. ΣFx = 0
   3. ΣFy = 0
   4. All of above
7. The line along which a force acts is called:
   1. line of action
   2. resultant force
   3. head to tail rule
   4. All of these
8. When the weight of a paratrooper becomes equal to the air resistance, what happens to his motion?
   1. He moves down with constant velocity
   2. He moves down with constant force
   3. He moves down with constant acceleration
   4. None of these
9. A satellite travels a distance equal to the circumference of a circle.
   1. 2πr
   2. 2π
   3. 3π
   4. 4π
10. The position of the centre of gravity depends upon:
    1. Size of the body
    2. Shape of the body
    3. Weight of the body
    4. Force of the body