$$d = 20 \times 10 = 200\ \mathrm{m}$$

Question 1

A 2 kg object is acted upon by two forces: 5 N to the right and 3 N to the left. What is the acceleration of the object?

Accepted Answer

$$a = \frac{5 - 3}{2} = 1\ \mathrm{m/s^2$} to $$the right

Question 2

Which of the following statements about inertia is correct?

Accepted Answer

Inertia is a property of matter that resists changes in motion.

Question 3

A car travels at a constant speed of 20 m/s for 10 seconds. How far does it travel?

Accepted Answer

$$d = 20 	imes 10 = 200\ \mathrm{m}$$

Question 4

If the net force on a 10 kg object is 50 N, what is its acceleration?

Accepted Answer

$$a = \frac{50}{10} = 5\ \mathrm{m/s^2$}$$

Question 5

A ball is thrown straight up. What is the velocity of the ball at its maximum height?

Accepted Answer

It is zero.

Question 6

Which of the following best describes the relationship between mass and inertia?

Accepted Answer

The greater the mass, the greater the inertia.

Question 7

A 0.5 kg ball is dropped from rest. Neglecting air resistance, what is its acceleration as it falls?

Accepted Answer

$$a = 9.8\ \mathrm{m/s^2$}$$

Question 8

A skydiver reaches terminal velocity when:

Accepted Answer

The net force on the skydiver is zero.

Question 9

Which of the following is a vector quantity?

Accepted Answer

Velocity

Question 10

A 3 kg object is moving at a constant velocity. What can you conclude about the net force acting on it?

Accepted Answer

The net force is zero.

Question 11

A 1 kg object is acted upon by a net force of 4 N. What is its acceleration, and in which direction does it act?

Accepted Answer

$$a = 4\ \mathrm{m/s^2$}$$, in the direction of the net force

Question 12

Which of the following best explains why a feather and a coin fall at the same rate in a vacuum?

Accepted Answer

There is no air resistance, so both experience the same acceleration due to gravity.

Question 13

A car accelerates from rest to 30 m/s in 10 seconds. What is its acceleration?

Accepted Answer

$$a = \frac{30}{10} = 3\ \mathrm{m/s^2$}$$

Question 14

Which of the following statements about friction is true?

Accepted Answer

Static friction is the force that resists the initiation of motion.

Question 15

A 2 kg object is in free fall near the surface of the Earth. What is the net force acting on it?

Accepted Answer

$$F = 2 	imes 9.8 = 19.6\ \mathrm{N}$$ downward

Question 16

Which of the following best describes terminal speed?

Accepted Answer

The speed at which the net force on a falling object is zero.

Question 17

A graph of position vs. time for an object moving at constant velocity will have what characteristic?

Accepted Answer

A straight line with constant slope.

Question 18

If a car is moving forward and the driver applies the brakes, what is the direction of the acceleration?

Accepted Answer

Backward

Question 19

Which of the following is true about the acceleration due to gravity near Earth's surface?

Accepted Answer

It is approximately $$9.8\ \mathrm{m/s^2$}$$ for all objects.

Question 20

A 4 kg object is pulled with a net force of 12 N. What is its acceleration?

Accepted Answer

$$a = \frac{12}{4} = 3\ \mathrm{m/s^2$}$$

Fundamentals of Newtonian Mechanics: Forces, Motion, and Acceleration

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