Question 1

A box of mass $$m$$ rests on a horizontal table. Which of the following best describes the direction and nature of the normal force acting on the box?

Accepted Answer

The normal force acts upward, equal to the weight of the box.

Question 2

A 2 kg block is pulled by a spring horizontally on a frictionless surface. If the spring exerts a force of 10 N, what is the acceleration of the block?

Accepted Answer

$$a = \frac{10}{2} = 5\ \mathrm{m/s^2$}$$

Question 3

Which of the following statements about tension force in a rope is correct?

Accepted Answer

Tension force always acts along the rope, away from the object being pulled.

Question 4

A car of mass $$1200\ \mathrm{kg}$$ has a maximum acceleration of $$4.0\ \mathrm{m/s^2$}$$ with only the driver. If four passengers and luggage add $$400\ \mathrm{kg}$$, what is the new maximum acceleration with the same net force?

Accepted Answer

$$a = \frac{F}{1600} = 3.0\ \mathrm{m/s^2$}$$

Question 5

Which of the following best describes the weight force acting on an object?

Accepted Answer

It is the gravitational pull of the Earth, always directed downward.

Question 6

A ball rolls off a horizontal ramp and flies through the air. Ignoring air resistance, which force(s) act on the ball just after it leaves the ramp?

Accepted Answer

Only the weight of the ball acting vertically downward.

Question 7

Which equation correctly expresses Newton’s Second Law for an object subjected to multiple forces?

Accepted Answer

$$\vec{F}_{\mathrm{net}} = m\vec{a}$$

Question 8

A crate is at rest on a rough surface. Which force prevents it from sliding when a small horizontal force is applied?

Accepted Answer

Static friction force

Question 9

A glider of unknown mass $$m_1 is $$pulled with the same tension force as a $$0.5\ \mathrm{kg}$$ glider, but accelerates at $$0.6\ \mathrm{m/s^2$}$$ while the $$0.5\ \mathrm{kg}$$ glider accelerates at $$1.0\ \mathrm{m/s^2$}. $$What is $$m_1$$?

Accepted Answer

$$m_1 = 0.83$$\ \mathrm{kg}$$

Question 10

Which of the following is true about the direction of the friction force acting on a sliding object?

Accepted Answer

It acts parallel to the surface, opposite to the direction of motion.

Question 11

A rocket is propelled forward by a thrust force. What is the agent responsible for this force?

Accepted Answer

The exhaust gases expelled backward

Question 12

Which of the following best describes the process for finding the sum of two force vectors?

Accepted Answer

Draw the vectors with their tails together, complete the parallelogram, and draw the resultant along the diagonal.

Question 13

A book rests on a table. What causes the normal force exerted by the table on the book?

Accepted Answer

Compression of molecular 'springs' in the table

Question 14

Which of the following is a correct statement about equilibrium?

Accepted Answer

The net force acting on the object is zero: $$\vec{F}_{\mathrm{net}} = 0$$

Question 15

A leaf falls slowly to the ground. Which force is primarily responsible for its slow descent?

Accepted Answer

Drag force (air resistance)

Question 16

If the net force on an object is doubled, what happens to its acceleration, assuming mass remains constant?

Accepted Answer

Acceleration doubles

Question 17

A person pushes horizontally on a wall but the wall does not move. What force does the wall exert on the person’s hand?

Accepted Answer

A normal force equal and opposite to the push

Question 18

Which of the following is NOT a contact force?

Accepted Answer

Weight (gravitational force)

Question 19

A block slides down a ramp. Which forces act on the block during its motion?

Accepted Answer

Weight, normal force, and friction force

Question 20

A spring is compressed by a force $$F. $$What happens when the force is removed?

Accepted Answer

The spring returns to its original shape due to its restoring force.

Forces and Newton's Second Law: Combination, Types, and Applications

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