Force Physics Practice

Get the force physics practice you need to get an A. Generate a 10 or 20 question quiz from this unit and find other useful practice.

This is an extensive unit. For more specific force practice, follow this link to a list of unit sections. Each section will have a physics practice quiz at the bottom of the page.

Use our equation sheet for guidance on the force equations. This unit uses one dimensional section, force section, and trigonometry reminders section of the equation sheet.

Physics Equation Sheet

Random 10 Questions from the Force Test Bank

10 - Forces Questions

1 / 10

What is the acceleration of a 1400 N skydiver at terminal velocity?

0 m/s/s

9.8 m/s/s down

9.8 m/s/s up

No net force and no acceleration at terminal velocity

2 / 10

What is the weight of a 1400 N skydiver at terminal velocity?

0 N

1400 N up

1400 N down

The way the question was stated it was giving you weight which is a force (F_w = 1400 N)

3 / 10

What is the acceleration of a 1400 N skydiver when she encounters 600 N of air resistance? (use g = 9.8 m/s/s)

9.8 m/s/s

0 m/s/s

4.5 m/s/s

5.6 m/s/s

Find Net Force

1400 N weight, which is a vector, directed down and mathematically -1400
600 N air resistance is opposite of motion so up and mathematically is +600
add the vectors together with their signs to get net force
-1400 + 600 = - 800 N or 800 N down

Find Mass

F_w = mg
m =F_w/g
m = 1400/9.8 = 143 kg

Calculate acceleration

F_net= ma

a = F_net/m

a = 800/143 = 5.6 m/s²

4 / 10

What is the acceleration of a 1400 N skydiver that has no air resistance?

0 m/s/s down

9.8 m/s/s down

5 m/s/s down

6.4 m/s/s down

When air resistance on earth is ignored and an object is not too high up, the acceleration due to gravity is 9.8 m/s/s

5 / 10

You use a spring scale to measure the amount of force required to first start an object moving. You would use this value to determine the coefficient of ___________ friction.

static

kinetic

Coefficient of static friction. The moment the object first starts moving is also almost equivalent to the maximum force provided by friction while the object was at rest or static.

6 / 10

Which is almost always greater

kinetic friction

static friction

rolling friction

When an object is at rest (static) the surfaces between objects are settled and closer together. With surfaces closer together there is more interaction and therefore more static friction friction than kinetic.

7 / 10

What is the magnitude of frictional force when 162 N of force is required to keep an object in constant motion?

0 n

10 N

16.2 N

162 N

What is the magnitude of frictional force when 162 N of force is required to keep an object in constant motion?

If there is constant motion there is no acceleration and the net force is zero. The frictional force must equal the force applied in the opposite direction so 162 N as well

8 / 10

What is the downhill force on a 4.0 kg object on a 25° Incline Plane?

0.41 N

4.0 N

16.6 N

35.5 N

9 / 10

What is the Normal force on a 4.0 kg object on a 25° Incline Plane?

0.41 N

4.0 N

16.6 N

35.5 N

10 / 10

Which number above is where the incline angle would be placed?

Your score is

LinkedIn Facebook Twitter

Random 20 Questions from the Force Test Bank

20 - Forces Questions

1 / 20

What is the spring constant of a spring displaced 0.1 meters when 400 N of force is applied?

40 N/m

4000 N/m

384 N/m

10 N/m

2 / 20

Solve for the tension in one of the ropes suspending the object above.

5.4 N

7.35 N

8.5 N

10.3 N

3 / 20

What is the tension in each of two ropes vertically suspending a 45 kg object? (use g = 9.8 m/s/s)

45 kg

441 N

0.218 N

221 N

Tension if a single rope would have the equal magnitude to the weight down. With two ropes both directed up, they are sharing the weight so divide by two.

F_w = mg

F_w = (45)(9.8) = 441 N

441/2 = 220.5 N

4 / 20

What is the tension in a rope when you apply a force of 100 N to pull an object forward in constant motion.

0 N

100 N backward

10 N backward

100 N forward

10 N forward

5 / 20

What is the weight of a 1400 N skydiver at terminal velocity?

0 N

1400 N up

1400 N down

The way the question was stated it was giving you weight which is a force (F_w = 1400 N)

6 / 20

What is net force of a 1400 N skydiver at terminal velocity?

0 N

1400 N up

1400 N down

At terminal velocity a person is no longer accelerating so net force is zero because air resistance force is equal to the weight force

7 / 20

What is the acceleration of a 1400 N skydiver that has no air resistance?

0 m/s/s down

9.8 m/s/s down

5 m/s/s down

6.4 m/s/s down

When air resistance on earth is ignored and an object is not too high up, the acceleration due to gravity is 9.8 m/s/s

8 / 20

Acceleration and mass are ______________ related

directly

inversely

9 / 20

What is the net force in the picture above

7 N right

22 N right

8 N left

52 N left

30 left is -30
15 right is +15
7 right is +7

Add them together and turn the sign back into a direction (-30 + 15 + 7 = -8)

8 Newtons Left

10 / 20

What is the acceleration on a 5 kg object that has a force of 20 N applied to the right and 5 newtons applied to the left?

5 m/s/s right

3 m/s/s left

5 m/s/s left

3 m/s/s right

11 / 20

What would happen to your weight if you were on a planet with twice the acceleration due to gravity?

It would half

It would double

It would stay the same

It would quadruple

12 / 20

Joe has a mass of 54 kg. What is his mass on the moon where the acceleration due to gravity is 1.62 m/s²?

539 kg

87.5 kg

54 kg

5.51 kg

Mass does not change. Weight does depending on the acceleration due to gravity.

13 / 20

Which has more inertia?

0.34 kg ball

40 kg calf

80 kg boy

Mass is directly related to inertia. The more the mass the more the inertia

Force applied equals the magnitude of force of friction in constant motion. If you find the force of friction (F_f), you know the Force applied (F_A)

14 / 20

What is the force required to keep a 0.5 kg brick in constant motion on a wood surface?

0 N

0.45 N

2.2 N

2.9 N

10.9 N

15 / 20

You use a spring scale to measure the amount of force required to first start an object moving. You would use this value to determine the coefficient of ___________ friction.

static

kinetic

Coefficient of static friction. The moment the object first starts moving is also almost equivalent to the maximum force provided by friction while the object was at rest or static.

16 / 20

What is the magnitude of frictional force when 162 N of force is required to keep an object in constant motion?

0 n

10 N

16.2 N

162 N

What is the magnitude of frictional force when 162 N of force is required to keep an object in constant motion?

If there is constant motion there is no acceleration and the net force is zero. The frictional force must equal the force applied in the opposite direction so 162 N as well

17 / 20

What type of friction do you have while an object is at rest?

Static

Kinetic

Rolling

Static Friction: at rest

Kinetic Friction: moving and can be sliding or rolling which would have a lower coefficient of friction than sliding.

18 / 20

What is the Normal force on a 4.0 kg object on a 25° Incline Plane?

0.41 N

4.0 N

16.6 N

35.5 N

19 / 20

What is the acceleration of a moving object on a 4.0 kg object on a 25° Incline Plane that has a coefficient of friction with the object of 0.43?

0.325 m/s/s

0.56 m/s/s

4.15 m/s/s

11.5 m/s/s

First find the weight (F_w = mg)
Use the weight to find the parallel force down the hill
Use the weight to find the perpendicular force into the hill (also equal to the magnitude of normal force which will be used in the friction equation)
Use the normal force from the step above to figure out the force of friction (F_f = µF_n)
Find the net force (by finding the sum of the forces) subtracting friction uphill from the parallel force downhill
Use the net force in the equation (F_net=ma) to determine the acceleration

20 / 20

Which letter above represents the parallel force?

Your score is

LinkedIn Facebook Twitter

Resources

StickMan Physics Home Page
Force Content Page
Stickman Physics Table of Contents: Use the search bar or click here to easily find a unit or topic
Physics Equation Sheet: commonly used equations, variables, and units
Rule of Ones: analyzing equations to determine how other variables change
Holdensclass.com: Video walk-through of Many Physics Concepts