Master Newton's Laws: Applications in Equilibrium, Friction, and More

Question 1

An object is said to be in equilibrium when:

Accepted Answer

The net force acting on it is zero.

Answer

The velocity of the object is constant.

Answer

The acceleration of the object is constant.

Answer

The object is not moving.

Question 2

A force of 10 N is applied to an object over a distance of 10 m. How much work is done by the force?

Accepted Answer

100 J

Answer

50 J

Answer

200 J

Answer

400 J

Question 3

Which of the following forces is non-conservative?

Accepted Answer

Friction

Answer

Gravitational force

Answer

Elastic force

Answer

Electrostatic force

Question 4

Which of the following is a vector quantity?

Accepted Answer

Velocity

Answer

Mass

Answer

Temperature

Answer

Volume

Question 5

A force of 10 N is applied at an angle of 30° to the horizontal. What is the horizontal component of the force?

Accepted Answer

8.66 N

Answer

5 N

Answer

10 N

Answer

17.32 N

Question 6

A 2 kg mass is attached to a spring with a spring constant of 200 N/m. The mass is pulled down 0.1 m below its equilibrium position and released. What is the maximum velocity of the mass?

Accepted Answer

0.4 m/s

Answer

0.2 m/s

Answer

0.8 m/s

Answer

1.6 m/s

Question 7

A pendulum of length 1 m swings with an amplitude of 0.2 m. What is the period of the pendulum?

Accepted Answer

2 s

Answer

1 s

Answer

4 s

Answer

8 s

Question 8

An elevator moves upward at a constant speed. The tension in the cable pulling the elevator up is 7000 N. What is the magnitude of the gravitational force acting on the elevator?

Accepted Answer

7000 N

Answer

14000 N

Answer

0 N

Answer

3500 N

Question 9

A 10 kg object rests on a horizontal surface with a coefficient of static friction of 0.2. What is the minimum horizontal force required to start the object moving?

Accepted Answer

20 N

Answer

30 N

Answer

10 N

Answer

40 N

Question 10

A 2 kg object moves in a circle of radius 5 m with a constant speed of 10 m/s. What is the magnitude of the centripetal force acting on the object?

Accepted Answer

40 N

Answer

80 N

Answer

60 N

Answer

20 N

Question 11

A 5 kg object is lifted vertically at a constant speed of 2 m/s. How much work is done by the lifting force on the object over a distance of 3 meters?

Accepted Answer

30 J

Answer

20 J

Answer

15 J

Answer

5 J

Question 12

A 0.5 kg ball is thrown vertically upward with an initial velocity of 10 m/s. Neglecting air resistance, what is the maximum height reached by the ball?

Accepted Answer

5.1 m

Answer

2.5 m

Answer

7.5 m

Answer

10 m

Question 13

A car with a mass of 1000 kg is traveling at a speed of 20 m/s. What is the kinetic energy of the car?

Accepted Answer

200 kJ

Answer

50 kJ

Answer

150 kJ

Answer

100 kJ

Question 14

A 2 kg block rests on a horizontal surface. A 10 N force is applied horizontally, causing the block to accelerate at 2 m/s². What is the magnitude of the frictional force acting on the block?

Accepted Answer

6 N

Answer

4 N

Answer

10 N

Answer

8 N

Question 15

A car travels at a constant speed around a circular track. Which statement best describes the forces acting on the car?

Accepted Answer

The net force is nonzero and directed towards the center of the circle.

Answer

The net force is nonzero and directed tangentially to the circle.

Answer

The net force is zero because the speed is constant.

Question 16

Two objects, one with twice the mass of the other, are dropped from the same height. Neglecting air resistance, which statement correctly describes their motion?

Accepted Answer

Both objects will hit the ground simultaneously with the same speed.

Answer

The heavier object will hit the ground first.

Answer

The lighter object will hit the ground first.

Question 17

A block slides down a frictionless inclined plane. What happens to its mechanical energy?

Accepted Answer

Its mechanical energy remains constant.

Answer

Its potential energy is converted into kinetic energy, but the total mechanical energy decreases.

Answer

Its potential energy is converted into kinetic energy, and the total mechanical energy increases.

Answer

Its kinetic energy is converted into potential energy, but the total mechanical energy decreases.

Question 18

A 10 kg object is suspended by two ropes at angles of 30° and 60° with the horizontal. What is the tension in the rope making a 30° angle with the horizontal?

Accepted Answer

50 N

Answer

85 N

Answer

98 N

Question 19

A car traveling at 20 m/s on a level road slams on its brakes and comes to a complete stop after skidding 40 meters. What is the coefficient of kinetic friction between the tires and the road?

Accepted Answer

0.5

Answer

2

Answer

1

Answer

0.25