9th Class Physics Chapter 3 Test3. Dynamics-I

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

1. The agency which changes or tends to change the state of rest or of uniform motion of a body:
   1. Weight
   2. Force
   3. Inertia
   4. Momentum
2. Net force is the:
   1. resultant force
   2. centripetal force
   3. Centrifugal force
   4. All of these
3. First law of motion is also known as law of:
   1. Torque
   2. Acceleration
   3. Inertia
   4. None of these
4. Which of the following is the unit of momentum?
   1. Nm
   2. kgms-1
   3. Ns
   4. Both b & c
5. When a hanging carpet is beaten by stick. Dust flies off the carpet. It is mainly due to.
   1. Action force on carpet
   2. Reaction force by carpet
   3. Inertia of dust
   4. Rate of change of momentum of carpet
6. The value of Gravitational field strength on earth:
   1. g = 9.8 N/kg
   2. g = 8.8 N/kg
   3. g = 10.8 N/kg
   4. g = 7.8 N/kg
7. The mass of the body is a measure of its:
   1. Inertia
   2. Weight
   3. Rest
   4. Acceleration
8. The rate of change of momentum of free falling body is equal to its.
   1. Momentum
   2. Velocity
   3. Weight
   4. Size
9. An object has a mass of 15 kg. It is pushed horizontally by a force of 40N. The frictional force is 10N. What is the acceleration of the object?
   1. 0.50 m/s²
   2. 1.5 m/s²
   3. 2.0 m/s²
   4. 2.7 m/s²
10. Inertia of a body is related to which of the following quantities.
    1. Mass
    2. Force
    3. Weight
    4. Friction