Chapter 3: Dynamics – I

1

Unit of gravitational field strength N/kg is equivalent to:

A m/s B m/s² C kg/m D N/m

2

Which has more inertia?

A Empty cart B Loaded cart C Football D Tennis ball

3

Weight of a body on the Moon is:

A Same as Earth B Zero C More than Earth D Less than Earth

4

Value of gravitational field strength on Earth is approximately:

A 1 N/kg B 4.9 N/kg C 9.8 N/kg D 98 N/kg

5

Which is NOT a fundamental force?

A Gravitational B Electromagnetic C Strong nuclear D Frictional

6

Which is a non-contact force?

A Friction B Tension C Gravitational force D Normal reaction

7

Zayn is studying Newton's third law. He learns that action and reaction forces act on different objects. Which of the following correctly describes action-reaction pair?

A Action force is greater than reaction force B Action and reaction forces act on the same object C Action and reaction forces are equal and opposite D Action force acts only on Earth

8

George is learning about Newton's second law of motion. He understands that force equals mass times acceleration (F = ma). If a 10 kg object is accelerated at 2 m/s², what is the force acting on it?

A 5 N B 20 N C 12 N D 10 N

9

Hina is learning about Newton's second law. She understands that F = ma. What is the acceleration of a 2 kg object when a force of 6 N is applied?

A 2 m/s² B 3 m/s² C 4 m/s² D 12 m/s²

10

Omar is learning about types of forces. He knows that tension is a force transmitted through a string or rope. Which of the following is an example of tension?

A Pulling a rope in a tug-of-war B A book resting on a table C A ball falling D A magnet attracting a nail

11

Usman is studying conservation of momentum. He learns that in a collision, the total momentum is conserved. In an inelastic collision, what is conserved?

A Momentum only B Kinetic energy only C Both momentum and kinetic energy D Neither

12

Ethan is studying conservation of momentum. He learns that in a collision, momentum is conserved. In an elastic collision, which of the following is also conserved?

A Momentum only B Kinetic energy C Both momentum and kinetic energy D Neither

13

Which force is responsible for weight?

A Magnetic force B Electric force C Gravitational force D Nuclear force

14

Waleed is studying force and change in momentum. He understands that force changes momentum. If a force of 8 N acts for 2 seconds, what is the impulse?

A 8 Ns B 16 Ns C 24 Ns D 4 Ns

15

Ahmed is learning about force in his physics class. His teacher explains that force is a push or pull that can change the state of motion of an object. Which of the following is an example of a force?

A Pushing a door open B The color of a car C The mass of an object D The temperature of a room

16

Paula is studying contact forces. She understands that normal force is a contact force that acts perpendicular to a surface. What is the normal force on a 20 kg object resting on a horizontal surface? (Take g = 10 m/s²)

A 20 N B 200 N C 10 N D 100 N

17

Julia is learning about mass and weight. She understands that mass is scalar and weight is vector. On the moon, how does the mass of an object change compared to Earth?

A It increases B It decreases C It remains the same D It becomes zero

18

Diana is studying impulse. She understands that impulse is also equal to the area under a force-time graph. If a force of 5 N is applied for 4 seconds, what is the impulse?

A 15 Ns B 20 Ns C 25 Ns D 10 Ns

19

Carlos is learning about force and change in momentum. He understands that a force changes the momentum of an object. If a force of 4 N acts on an object for 5 seconds, what is the change in momentum?

A 20 Ns B 10 Ns C 25 Ns D 15 Ns

20

George is studying Newton's first law. He understands that an object in motion stays in motion unless acted upon by an unbalanced force. What does this law imply about the motion of a book on a table?

A The book will move on its own B The book will remain at rest unless a force acts on it C The book will accelerate continuously D The book will fly away

21

If net force on a body is not zero, body will:

A Remain at rest B Move with constant velocity C Accelerate D Stop moving

22

Rania is studying net force. She understands that net force is the vector sum of all forces. If forces of 8 N and 6 N act at right angles to each other, what is the magnitude of the net force?

A 10 N B 14 N C 48 N D 2 N

23

In free body diagram, forces are shown by:

A Lines B Dots C Arrows D Circles

24

Tina is learning about impulse. She understands that impulse is force multiplied by time. If the force is doubled and the time is halved, what happens to the impulse?

A It doubles B It halves C It remains the same D It quadruples

25

Force is a vector quantity because it has:

A Magnitude only B Direction only C Magnitude and direction D No unit