AnswersPhysicsForces, Newton's Laws, and Momentum

Forces, Newton's Laws, and Momentum — Test Answers

25 verified answers
1
Free Preview

Question text not available

Answer:

8.8

2
Free Preview

What best describes the blocks after the spring is released?

A
The momentum of the m block is zero.
B
The momentum of the 2 m block is zero.
C
The total energy is zero.
D
The total momentum is zero.
3

What is the magnitude of the force of tension if the net force in the x direction of 98 cap n ?

A
98 cap n
B
57 cap n
C
183 cap n
D
139 cap n
4

Which trial has the greatest impulse?

A
trial 1
B
trial 2
C
trial 3
D
trial 4
5

Which best describes the friction acting on the piano?

A
The kinetic frictional force is greater than the static frictional force, so the kinetic frictional force is greater than 1200 N.
B
The static and kinetic friction are both equal to the gravitational force of 2200 N.
C
The static and kinetic frictional forces are equal, so the static frictional force is equal to 1200 N.
D
The static frictional force is greater than the kinetic frictional force, so the static frictional force is greater than 1200 N.
6

Which object has a net force of negative 5 cap n down?

A
cap w
B
cap x
C
cap y
D
cap z
7

To the nearest whole number, what is the force of tension, cap f sub f , acting on the elevator?

A
15 comma 150 cap n
B
14 comma 250 cap n
C
450 cap n
D
1500 cap n
8

Which graph best represents the momentum of both carts over time, before and after the collision?

A
Image with description A graph with momentum on the y axis measured in kilogram meters per second and time on the x axis measured in seconds. There are no values on the axes. There are two curves on the graph the first starts above the x axis and is horizontal before curving downward toward the x axis labeled 2 m cart. The second curve starts below the axis, a smaller distance below as the first one was above, and is horizontal before curving upward toward and crosses the x axis and is labeled m cart. Where they meet is labeled Collision. Both curves meet above the axis at the same time and both go horizontal above the x axis for a time period labeled Combined carts.
B
Image with description A graph with momentum on the y axis measured in kilogram meters per second and time on the x axis measured in seconds. There are no values on the axes. There are two curves on the graph. The first starts above the x axis and is horizontal before curving downward to the x axis labeled 2 m cart. The second curve starts below the axis, the same distance below as the first one was above, and is horizontal before curving upward toward the x axis at the same time and labeled m cart. Where they meet is labeled Collision. Both curves meet at the x axis at the same time and are both on the x axis for a time period labeled Combined carts.
C
Image with description A graph with momentum on the y axis measured in kilogram meters per second and time on the x axis measured in seconds. There are no values on the axes. There are two curves on the graph the first starts above the x axis and is horizontal before curving downward toward the x axis labeled 2 m cart. The second curve starts below the axis, a smaller distance below as the first one was above, and is horizontal before curving upward toward and crosses the x axis and is labeled m cart. Where they meet is labeled Collision. Both curves meet above the axis at the same time and both go horizontal above the x axis for a time period labeled Combined carts.
D
Image with description A graph with momentum on the y axis measured in kilogram meters per second and time on the x axis measured in seconds. There are no values on the axes. There are two curves on the graph. The first starts above the x axis and is horizontal before curving downward to the x axis labeled 2 m cart. The second curve starts below the axis, the same distance below as the first one was above, and is horizontal before curving upward toward the x axis at the same time and labeled m cart. Where they meet is labeled Collision. Both curves meet at the x axis at the same time and are both on the x axis for a time period labeled Combined carts.
9

Which motor and body should Devon use to build the car with the greatest acceleration?

A
motor 2, with body 2
B
motor 1, with body 2
C
motor 2, with body 1
D
motor 1, with body 1
10

Which shows the correct free body diagram of the hanging picture?

A
Image with description A free body diagram with two force vectors, the first pointing downward labeled F Subscript p Baseline, the second pointing upward labeled F Subscript T Baseline.
B
Image with description A free body diagram with three force vectors, the first pointing south labeled F Subscript g Baseline, the second pointing northeast labeled F Subscript T Baseline and the third pointing northwest labeled F Subscript T.
C
Image with description A free body diagram with three force vectors, the first pointing south labeled F Subscript p Baseline, the second pointing northeast labeled F Subscript T Baseline, and the third pointing northwest labeled F Subscript N.
D
Image with description A free body diagram with two force vectors, the first pointing downward labeled F Subscript g Baseline, the second pointing upward labeled F Subscript N Baseline.
11

According to Newton’s first law of motion, what will an object in motion do when no external force acts on it?

A
move at the same velocity
B
come to a stop
C
change direction
D
speed up
12

Juanita studies several free-body diagrams in which a normal force is shown. What is always true about a normal force in a free-body diagram?

A
It is opposite the net force.
B
It is perpendicular to a surface.
C
It is parallel to a surface.
D
It is opposite the weight.
13

A ball is dropped from rest from the top of a building. What force is responsible for the downward motion of the ball?

A
the force of tension
B
the normal force
C
the force of gravity
D
the pushing force
14

A sports car and a minivan run out of gas and are pushed to the side of the road. Which is easier to push, and why?

A
the minivan, because it has less mass and therefore less inertia
B
the sports car, because it has less mass and therefore less inertia
C
the minivan, because it has more mass and therefore more inertia
D
the sports car, because it has more mass and therefore more inertia
15

A 225 kilograms red bumper car is moving at 3.0 meters per second It hits a stationary 180 kilograms blue bumper car. The red and blue bumper cars combine and hit a stationary green bumper car of mass 150 kilograms The red, blue, and green bumper cars all combine. What is the final velocity of the combined bumper cars?

A
1.7 meters per second
B
1.2 meters per second
C
2.7 meters per second
D
0.93 meters per second
16

Two grocery carts have the same initial total momentum. The two carts collide, and now cart B has a greater final velocity. Which best describes the final total momentum of both the carts compared to the initial total momentum?

A
It is less if cart B has a smaller mass.
B
It is the same if no external forces are added.
C
It is greater if cart B has a greater mass.
D
It depends on the masses of cart A and cart B.
17

Kamala puts on inline skates and stands facing a wall. When she pushes against the wall, she rolls backward. Why does pushing harder make her roll faster?

A
The force of the wall pushing on her increases.
B
The additional force decreases her weight.
C
The force of friction between the wheels and the ground decreases.
D
The extra force causes an increase of the normal force from the ground.
18

A boy and his skateboard have a combined mass of 65 kilograms What is the speed of the boy and skateboard if they have a momentum of 275 kilograms times m over s ?

A
8.5 meters per second
B
0 meters per second
C
0.24 meters per second
D
4.2 meters per second
19

A baseball has a mass of 0 point 4 5 kilograms and is thrown with a speed of 25 meters per second What is the momentum of the baseball?

A
140 kilograms times m over s
B
11 kilograms times m over s
C
56 kilograms times m over s
D
0 point 0 1 8 kilograms times m over s
20

For problems that involve an object accelerating along an inclined plane, how can the weight be used to determine the force component that causes motion?

A
The weight times the cosine of the ramp’s angle is the force perpendicular to the ramp.
B
The weight is the full force that acts perpendicular to the surface of the ramp.
C
The weight times the cosine of the angle of the ramp acts down along the ramp.
D
The weight times the sine of the angle of the ramp acts down along the ramp.

Did you find these answers helpful?

More from this Course

Quiz
24 verified answers

Test

Quiz
22 verified answers

Test

Quiz
21 verified answers

Test