Question 1

A 30 kg box is being dragged horizontally at constant velocity with a rope. The coefficient of friction between the box and the surface is 0.3. What is the normal force acting on the box? (Assume $$g = 10 \ \mathrm{m/s^2$})$$

Accepted Answer

$$300 \ \mathrm{N}$$

Question 2

A horizontal, uniform board of weight $$100 \ \mathrm{N} is $$hanging from the ceiling by vertical chains at each end. A person weighing $$750 \ \mathrm{N} is $$also hanging from the middle of the board. If the tension in the right chain is $$400 \ \mathrm{N}$$, what is the tension in the left chain?

Accepted Answer

$$450 \ \mathrm{N}$$

Question 3

A dolphin swims $$15$$ miles north in $$2$$ hours, floats for $$0.5$$ hours, then swims $$45$$ miles south in $$1.5$$ hours. What is the magnitude of the dolphin’s displacement and the total distance traveled?

Accepted Answer

Displacement: $$30 mi$$, Distance: $$60 mi$$

Question 4

Which of the following correctly indicates the dolphin’s average speed and average velocity over the trip described above?

Accepted Answer

Average speed: $$15$$ mph, Average velocity: $$7.5$$ mph

Question 5

A box is pushed rightward with a force $$F at $$constant velocity across a surface with friction, while a force $$P$$ pushes down on the box. Which free body diagram correctly represents the forces acting on the box?

Accepted Answer

Diagram (C): Normal force up, friction left, applied force right, weight and $$P$$ down (correct)

Question 6

A car’s position vs. time graph shows three segments: constant velocity, no motion, and constant velocity. Which statement about the net force on the car is true?

Accepted Answer

The net force is the same at all three times.

Question 7

A position-time graph for an object is a straight line with a positive slope. Which of the following velocity-time graphs best represents the motion?

Accepted Answer

A horizontal line above the time axis

Question 8

Given the velocity-time graphs for two robots, Case A and Case B, which case has the greater magnitude of displacement over the time interval shown?

Accepted Answer

Case B

Question 9

A box is being pushed across the floor with a constant speed. Which of the following statements is true about the forces acting on the box?

Accepted Answer

The applied force is equal to the friction force.

Question 10

A student claims that force is proportional to mass. What would you expect to see if you graphed force (y-axis) versus mass (x-axis) for several measurements, assuming the claim is correct?

Accepted Answer

A linear graph with a y-intercept of zero

Question 11

Which of the following position-time graphs shows an object moving with constant velocity?

Accepted Answer

A straight line with positive slope

Question 12

A $$30 \ \mathrm{kg}$$ box is being dragged at constant velocity. If the coefficient of friction is $$0.3$$, what is the magnitude of the friction force?

Accepted Answer

$$90 \ \mathrm{N}$$

Question 13

Which of the following best describes the relationship between the normal force $$F_N$$, the downward force $$P$$, and the gravitational force $$F_g$$ for a box on a surface?

Accepted Answer

$$F_N = P + F_g$$

Question 14

A motion-dot diagram shows an object moving left and then slowing down. Which velocity-time graph best represents this motion (left is negative, right is positive)?

Accepted Answer

A line starting negative and moving toward zero

Question 15

Rank the average speed of the objects in the position-time graphs (A, B, C, D) from greatest to least, given the total distance traveled over 4 seconds.

Accepted Answer

D \u003e C \u003e B \u003e A

Question 16

Which of the following is true for an object sliding at constant speed across the floor with nothing touching it?

Accepted Answer

The only forces acting are the normal force and gravity.

Question 17

If an object’s position-time graph is a horizontal line, what can you say about its velocity?

Accepted Answer

The velocity is zero.

Question 18

A position-time graph shows an object moving away from the origin, then returning to the origin. What is the displacement after the entire trip?

Accepted Answer

Zero

AP Physics 1 Unit 1 Test Review – Step-by-Step Study Guidance

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