D Answer 600 m/s C 0.003 m/s D [This object is a pull tab] - - PDF document

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8th Grade

Forces and Motion

Study Guide www.njctl.org

Slide 2 / 40 1

A snail travels 10 m in 3000 seconds. What is the snail's average speed?

A

60000 m/s

B

0.02 m/s

C

600 m/s

D

0.003 m/s

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1

A snail travels 10 m in 3000 seconds. What is the snail's average speed?

A

60000 m/s

B

0.02 m/s

C

600 m/s

D

0.003 m/s

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Answer

D

Slide 3 (Answer) / 40 2

A blimp travels at 3 m/s for 1000 s. What distance does the blimp cover in that time?

A

500 m/s

B

3000 m

C

4500 m/s

D

500 m

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A blimp travels at 3 m/s for 1000 s. What distance does the blimp cover in that time?

A

500 m/s

B

3000 m

C

4500 m/s

D

500 m

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Answer

B

Slide 4 (Answer) / 40

3 When your teacher times your mile run at 8.2

minutes, that means your speed was 0.12 mi/min. Was this your average speed or your instantaneous speed?

A Average Speed B Instantaneous Speed

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3 When your teacher times your mile run at 8.2

minutes, that means your speed was 0.12 mi/min. Was this your average speed or your instantaneous speed?

A Average Speed B Instantaneous Speed

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Answer

avg speed = 8.2mi/min

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4 Does a speedometer measure the average speed or

the instantaneous speed?

A Average Speed B Instantaneous Speed

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4 Does a speedometer measure the average speed or

the instantaneous speed?

A Average Speed B Instantaneous Speed

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Answer

Instantaneous Speed

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5 A swordfish travels for two hours. The first hour he covers 110 kilometers, and the second hour he covers 110 kilometers. What is the average speed of the swordfish? A 55 km/h B 84 km/h C 110 km/h D 194 km/h

Hint: Remember that average speed is total distance travelled divided by total time

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5 A swordfish travels for two hours. The first hour he covers 110 kilometers, and the second hour he covers 110 kilometers. What is the average speed of the swordfish? A 55 km/h B 84 km/h C 110 km/h D 194 km/h

Hint: Remember that average speed is total distance travelled divided by total time

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Answer

C

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6 A dog walks outside to go the bathroom every day. If she walks outside at a speed of 3 meters per second and walks 150 meters before she uses the bathroom, how long does it take her? A 50 seconds B 2 minutes C 188 seconds D 90 seconds

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6 A dog walks outside to go the bathroom every day. If she walks outside at a speed of 3 meters per second and walks 150 meters before she uses the bathroom, how long does it take her? A 50 seconds B 2 minutes C 188 seconds D 90 seconds

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Answer

A

Slide 8 (Answer) / 40

7 Carlos and Gina are riding on their horses to go into

• town. They travel 140 meters in 14 seconds going
• west. What is their velocity?

A 490 m/s west B 10 m/s west C 490 m/s D 10 m/s

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7 Carlos and Gina are riding on their horses to go into

• town. They travel 140 meters in 14 seconds going
• west. What is their velocity?

A 490 m/s west B 10 m/s west C 490 m/s D 10 m/s

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Answer

B

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8 A car travels 200 km/h west for 2 hours. The car then travels 150 km/h east for one hour. What is the car's position relative to its starting position? A 50 km west B 150 km west C 250 km west D 50 km east

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8 A car travels 200 km/h west for 2 hours. The car then travels 150 km/h east for one hour. What is the car's position relative to its starting position? A 50 km west B 150 km west C 250 km west D 50 km east

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Answer

C

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9

A nitro-methane powered top fuel dragster launches from rest to race against an opponent. Why did the car accelerate?

A

increased speed

B

decreased speed

C

changed direction

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A nitro-methane powered top fuel dragster launches from rest to race against an opponent. Why did the car accelerate?

A

increased speed

B

decreased speed

C

changed direction

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Answer

A

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10 A driver hits the brakes to slow down at an

• intersection. As the car's speed is decreasing it has

A positive acceleration B negative acceleration C no acceleration D more information is needed

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10 A driver hits the brakes to slow down at an

• intersection. As the car's speed is decreasing it has

A positive acceleration B negative acceleration C no acceleration D more information is needed

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Answer

B

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11 Which of the following graphs depicts the

acceleration of a runner speeding up to pass someone. A B C

x

Y

Speed (m/s) Time (s) x

Y

Speed (m/s) Time (s)

x

Y

Speed (m/s) Time (s)

D

x

Y

Speed (m/s) Time (s)

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11 Which of the following graphs depicts the

acceleration of a runner speeding up to pass someone. A B C

x

Y

Speed (m/s) Time (s) x

Y

Speed (m/s) Time (s)

x

Y

Speed (m/s) Time (s)

D

x

Y

Speed (m/s) Time (s)

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Answer

C

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12 Which of the following speed vs time graphs corresponds to the position vs time graph shown in the graph below?

A B C

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12 Which of the following speed vs time graphs corresponds to the position vs time graph shown in the graph below?

A B C

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Answer

A

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13 A ball is traveling down a hill at 4 m/s. If the ball increases in speed to 8 m/s in 4 seconds, what is the acceleration of the ball? A 4 m/s B 4 m/s/s C 1 m/s D 1 m/s/s

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13 A ball is traveling down a hill at 4 m/s. If the ball increases in speed to 8 m/s in 4 seconds, what is the acceleration of the ball? A 4 m/s B 4 m/s/s C 1 m/s D 1 m/s/s

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Answer

D

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14 Forces are all around us. Which of the following do you think are examples of forces? (choose all that apply) A Gravity B Friction C Muscles D Wind

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14 Forces are all around us. Which of the following do you think are examples of forces? (choose all that apply) A Gravity B Friction C Muscles D Wind

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Answer

A & B

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15 What is the SI unit for force? A Pounds B Kilograms C Newtons

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15 What is the SI unit for force? A Pounds B Kilograms C Newtons

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Answer

C

Slide 17 (Answer) / 40 16 A +20 N force acts on a car and at the same time,

a -30 N force acts on the car. What is the net force acting on the car and is it balanced? A

• 30 N unbalanced

B

• 10 N unbalanced

C

• 10 N balanced

D + 30 balanced

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16 A +20 N force acts on a car and at the same time,

a -30 N force acts on the car. What is the net force acting on the car and is it balanced? A

• 30 N unbalanced

B

• 10 N unbalanced

C

• 10 N balanced

D + 30 balanced

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Answer

B

Slide 18 (Answer) / 40 17 The force of gravitation between an object and a

planet is increased as they move away from each

• ther:

True False

Slide 19 / 40 17 The force of gravitation between an object and a

planet is increased as they move away from each

• ther:

True False

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Answer

False

Slide 19 (Answer) / 40

18 A 100 kg kid is on the moon, where g = 1.67 m/s2 .

What is the boy's weight? A 83.5 kg B 167 kg C 167 N D 29.9 N

Slide 20 / 40 18 A 100 kg kid is on the moon, where g = 1.67 m/s2 .

What is the boy's weight? A 83.5 kg B 167 kg C 167 N D 29.9 N

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Answer

C

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19 What is the net force acting on the object below?

7 N

• 8 N
• 10 N

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19 What is the net force acting on the object below?

7 N

• 8 N
• 10 N

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Answer

• 11 N

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20 Is the object in equilibrium? Yes No

7 N

• 8 N
• 10 N

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20 Is the object in equilibrium? Yes No

7 N

• 8 N
• 10 N

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Answer

No

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21 What is the net force acting on the object below?

25 N

• 15N
• 10 N

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21 What is the net force acting on the object below?

25 N

• 15N
• 10 N

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Answer

0 N

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22 Is the object in equilibrium? Yes No

25 N

• 15N
• 10 N

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22 Is the object in equilibrium? Yes No

25 N

• 15N
• 10 N

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Answer

Yes

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23 Acceleration due to gravity on Jupiter is 26.1 m/s2 . How much would a 25 kg person weigh on Jupiter?

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23 Acceleration due to gravity on Jupiter is 26.1 m/s2 . How much would a 25 kg person weigh on Jupiter?

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Answer

653 N

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24 Acceleration due to gravity on Earth's Moon is 1.67 m/s2 . How much would a 113 kg person weigh on Earth's Moon?

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24 Acceleration due to gravity on Earth's Moon is 1.67 m/s2 . How much would a 113 kg person weigh on Earth's Moon?

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Answer

189 N

Slide 26 (Answer) / 40 25 Inertia is the reluctance any material object has

to change its state of motion. True False

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25 Inertia is the reluctance any material object has

to change its state of motion. True False

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Answer

True

Slide 27 (Answer) / 40 26 The law of inertia applies to:

A moving objects B nonmoving objects C both moving and nonmoving objects

Slide 28 / 40 26 The law of inertia applies to:

A moving objects B nonmoving objects C both moving and nonmoving objects

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Answer

C

Slide 28 (Answer) / 40

27 Which object has the greatest inertia? A Car B Tennis Ball C Freight Train

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27 Which object has the greatest inertia? A Car B Tennis Ball C Freight Train

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Answer

C

Slide 29 (Answer) / 40 28 A ball will accelerate and increase its velocity

when it feels an unbalanced force. True False

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28 A ball will accelerate and increase its velocity

when it feels an unbalanced force. True False

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Answer

True

Slide 30 (Answer) / 40 29 When the force acting on an object decreases,

the resulting acceleration will: A remain constant B increase C decrease

Slide 31 / 40 29 When the force acting on an object decreases,

the resulting acceleration will: A remain constant B increase C decrease

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Answer

C

Slide 31 (Answer) / 40

30 When an object's mass is decreased but the

applied force stays the same, the resulting acceleration will: A remain constant B increase C decrease

Slide 32 / 40 30 When an object's mass is decreased but the

applied force stays the same, the resulting acceleration will: A remain constant B increase C decrease

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Answer

B

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31 You are riding your bicycle to the park to meet a few friends. As you ride, you apply a force of 40 N and accelerate at a rate of 0.4 m/s2 . What is the total mass of the bicycle and you? A 75 kg B 100 kg C 120 kg

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31 You are riding your bicycle to the park to meet a few friends. As you ride, you apply a force of 40 N and accelerate at a rate of 0.4 m/s2 . What is the total mass of the bicycle and you? A 75 kg B 100 kg C 120 kg

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Answer

B

Slide 33 (Answer) / 40 32 When you sit on a chair, the chair pushes back

with force equal to your weight. True False

Slide 34 / 40 32 When you sit on a chair, the chair pushes back

with force equal to your weight. True False

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Answer

True

Slide 34 (Answer) / 40

33 Which of the following statements pertains to the third law of motion? A Action and Reaction pairs always act on the same object. B Mass is indirectly proportional to acceleration. C An object at rest will remain at rest unless acted on by an unbalanced force. D If a force occurs, action reaction forces are present.

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33 Which of the following statements pertains to the third law of motion? A Action and Reaction pairs always act on the same object. B Mass is indirectly proportional to acceleration. C An object at rest will remain at rest unless acted on by an unbalanced force. D If a force occurs, action reaction forces are present.

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Answer

D

Slide 35 (Answer) / 40 34 How can a small toy have the same momentum as

a large car? A toy has large speed B both car and toy are at rest C toy has no mass D A & B

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34 How can a small toy have the same momentum as

a large car? A toy has large speed B both car and toy are at rest C toy has no mass D A & B

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Answer

D

Slide 36 (Answer) / 40 35 If a 3 kg toy truck is moving at 4 m/s, what is the

toy's momentum? A 3 m/s B 2 kgm/s C 12 kgm/s D 12 m/s

Slide 37 / 40 35 If a 3 kg toy truck is moving at 4 m/s, what is the

toy's momentum? A 3 m/s B 2 kgm/s C 12 kgm/s D 12 m/s

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Answer

C

Slide 37 (Answer) / 40

36 What two factors does momentum depend on? A mass and volume B mass and acceleration C mass and velocity D mass and force

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36 What two factors does momentum depend on? A mass and volume B mass and acceleration C mass and velocity D mass and force

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Answer

C

Slide 38 (Answer) / 40 37 The law of conservation of momentum states that

the total momentum after a collision increases from its value before the collision. True False

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37 The law of conservation of momentum states that

the total momentum after a collision increases from its value before the collision. True False

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Answer

False

Slide 39 (Answer) / 40

38 According to Newton's 3rd law, action reaction pairs are equal and opposite to each other. Why do these paired forces sometimes cause different motions if they are equal?

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38 According to Newton's 3rd law, action reaction pairs are equal and opposite to each other. Why do these paired forces sometimes cause different motions if they are equal?

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Answer

because they act on different

• bjects

Slide 40 (Answer) / 40