MCAS Motion and Forces 1

1.

1 point

Which of the following examples includes a vector quantity?

a 10.0 kg object

a truck that traveled 12.5 m

a 3.5 kg object moving at 1.5 m/s

a car moving northeast at 90 km/hr

2.

1 point

A car is parked on a flat driveway. Which of the following is a free-body diagram for this car?

A

B

C

D

3.

1 point

The free-body diagram below represents all the forces acting on an object.

What is the net force acting on this object?

0 N up

100 N down

200 N right

300 N right

4.

1 point

A toy truck powered by a battery is accelerating to the right. A string with negligible mass is attached to the truck. The diagram below shows the forces acting on the truck.

If a child pulls the string to the left, what force must the child exert to make the toy truck move to the right at a constant velocity?

1.0 N

1.5 N

2.5 N

6.0 N

5.

1 point

The Moon was much closer to Earth 4.6 billion years ago. Which of the following statements describes the gravitational interaction of Earth and the Moon 4.6 billion years ago?

The gravitational force of the Moon on Earth was larger than the force is now.

The gravitational force of Earth on the Moon was the same as the force is now.

The gravitational force of the Moon on Earth was smaller than the force is now.

The gravitational force of Earth on the Moon was smaller than the force is now.

6.

1 point

A person pushes a couch across a wooden floor. What force changes when the couch first begins to move?

frictional force

gravitational force

normal force

tension force

7.

1 point

A person runs 3 km north. One hour later, she runs 3 km south.
Which of the following statements describes the person’s complete trip?

The displacement is 3 km.

The distance traveled is 3 km.

The distance traveled is greater than the displacement.

The displacement is greater than the distance traveled.

8.

1 point

A space station moves in a circular orbit around Earth. Which of the following statements describes the centripetal force acting on the space station?

The force is acting in the direction of motion.

The force is directed toward the space station.

The force is directed toward the center of Earth.

The force is acting opposite the direction of motion.

9.

1 point

Which of the following is an example of an object that could have a net force greater than zero acting on it?

a glass resting on a table

a ball rolling down a ramp

a ladder leaning against a wall

a toy car moving east at a constant velocity

10.

1 point

The graph below represents the motion of a car.

Based on the graph, which of the following statements describes the motion of the car?

The car initially travels at a constant speed and then stops.

The car starts from rest and then travels at a constant speed.

The car starts from rest and then accelerates at a constant rate.

The car is initially moving and then accelerates at a constant rate.

11.

1 point

A rope is attached to a block that has a weight of 120 N. When the rope exerts an upward force of 250 N on the block, what is the net force on the block?

130 N up

370 N up

130 N down

370 N down

12.

1 point

A satellite in a circular orbit around Earth has a constant speed but not a constant velocity. Which of the following statements best explains why the satellite’s velocity is not constant?

The radius of the satellite’s orbit is too large.

The force on the satellite’s mass is constantly decreasing.

The magnitude of the satellite’s momentum is too large.

The direction of the satellite’s motion is constantly changing.

13.

1 point

An object is traveling in a straight line. The graph below shows the object’s velocity over time.

Which line segment shows the object traveling with a constant, positive acceleration?

segment W

segment X

segment Y

segment Z

14.

1 point

The diagram below represents a block sliding across a table at a constant speed. All forces are shown except the frictional force.

What is the magnitude of the frictional force on the block?

0.8 N

1.6 N

1.7 N

2.5 N

15.

1 point

The graph below represents the motion of an object over four time intervals, W, X, Y, and Z.

Over which time interval is the object moving the fastest?

interval W

interval X

interval Y

interval Z

16.

1 point

A person starts driving and travels 3 km east to a store. The person then turns around and travels 1 km west to another store. Finally, the person travels 2 km west, back to the starting point.
What distance has this person traveled?

0 km

3 km

5 km

6 km

17.

1 point

A student researches Jupiter and Saturn and records the following information:
-Jupiter is about half the distance to the Sun that Saturn is.
-Jupiter is about three times more massive than Saturn.
Based on this information, which of the following can be concluded about the gravitational forces between these planets and the Sun?

There are no gravitational forces between Jupiter and the Sun or between Saturn and the Sun.

There are equal gravitational forces between Saturn and the Sun and between Jupiter and the Sun.

There is a greater gravitational force between Jupiter and the Sun than between Saturn and the Sun.

There is a greater gravitational force between Saturn and the Sun than between Jupiter and the Sun.

18.

1 point

The diagram below shows a ball tied to a string. A student is swinging the ball in a horizontal circle.

If the student releases the string, in which direction will the ball travel?

direction W

direction X

direction Y

direction Z

19.

1 point

The graph below illustrates the motion of a toy car during time intervals X, Y, and Z. The toy car is initially at rest. It is then pushed and released.

Kinetic friction is acting on the toy car during which of the following time intervals?

interval X only

interval Y only

intervals X and Z

intervals Y and Z

20.

1 point

A worker in a warehouse pushes two wooden boxes across a floor at a constant speed, as shown in the diagram below.

The arrow in the diagram represents the force box 1 exerts on box 2. Which arrow represents the reaction force?

21.

1 point

A rock is dropped from a window 5 m above the ground. The rock hits the ground 1.0 s later with a speed of 10 m/s.
What is the average speed of the rock during this time?

5 m/s

8 m/s

15 m/s

50 m/s

22.

1 point

A person pushes a heavy cabinet across a level wooden floor. Force X is the force required to start the cabinet moving. Force Y is the force required to maintain a slow, steady forward motion.
Which of the following statements describes the two forces, X and Y?

Force X is added to force Y.

Force X is less than force Y.

Force X is unrelated to force Y.

Force X is greater than force Y.

23.

1 point

According to Newton’s law of universal gravitation, in which of the following situations does the gravitational attraction between two bodies always increase?

The masses increase, and the distance between the centers of mass increases.

The masses increase, and the distance between the centers of mass decreases.

The masses decrease, and the distance between the centers of mass increases.

The masses decrease, and the distance between the centers of mass decreases.

24.

1 point

Two soccer players, X and Y, are kicking a ball back and forth to each other, as shown below.

The table below shows the distance and direction the ball moves after each of four kicks.

What is the total displacement of the ball and the total distance traveled by the ball?

The ball has a displacement of 2 m to the right and traveled a distance of 20 m.

The ball has a displacement of 20 m to the right and traveled a distance of 2 m.

The ball has a displacement of 9 m to the right and traveled a distance of 11 m.

The ball has a displacement of 11 m to the right and traveled a distance of 9 m.

25.

1 point

A ball is thrown upward at an angle from position P. The diagram below shows the position of the ball at equal time intervals as it moves from position P to position Q.

Which of the following causes the change in the ball’s velocity as the ball travels from position P to position Q?

decrease in its inertia

increase in its momentum

downward force of gravity

initial acceleration upward