Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

8th and 9th Grade > Forces > Flashcards

Forces Flashcards

(65 cards)

Start Studying
1
Q

What do we need to use to know if an object is in motion?

A

A reference point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Reference Point

A

An object that is not moving to determine if an object is moving

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a force?

A

A push or pull

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The SI Unit for force

A

Newtons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many newtons are balanced forces?

A

0N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Net Force

A

The total or final force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the formula for speed?

A

Distance/time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The faster the object the _____ the line

A

Steeper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does a horizontal line on a graph mean?

A

The object not moving, the slope is 0.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does SI Stand for?

A

System International

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The SI unit for speed

A

Meters per second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Instantaneous Speed

A

The rate something is moving at a given instant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Velocity

A

Speed and direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Acceleration

A

Increasing speed, decreasing speed, and changing direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What two factors does the strength of friction depend on?

A

How hard the surfaces push each other & the types of surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Mass

A

The amount of matter in an object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Weight

A

The force of gravity on an object at the surface of planet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What two factors affect the gravitational attraction of two objects?

A

Mass and distance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Terminal Velocity

A

The greatest velocity that can be reached by an object in free fall.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Air resistance

A

The type of fluid friction that acts on objects as they move through a fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Friction

A

A force that opposes motion when two objects are in contact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why are units of measurement used?

A

To describe an objects motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Rate

A

The amount of something that occurs or changes in one unit of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do you find the speed for an object that’s not moving at a constant speed?

A

Find the average speed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
How do you find the average speed?
Divide the total distance traveled by the total time
25
What is the formula for force?
F = Mass x Acceleration
26
What is the basic SI unit of length
Meters
27
What does the prefix "milli-" mean?
One thousandth of the basic unit
28
How are Forces described?
How strong they are and in which direction they act
29
What part of forces are measured?
Its strength
30
How is the strength of a force measured?
Using the SI unit the newton
31
How is the Net Force found?
By combining all of the forces acting on the object
32
What kind of forces have a net force?
Unbalanced forces
33
What will unbalanced forces acting on an object do?
They can cause an object to start moving, stop moving, or change direction.
34
How do balanced forces affect an object's motion?
It will not change the objects motion
34
What is the net force of a balanced object's motion
0N
34
What are equal forces acting in opposite directions called?
Balanced forces
35
Friction
The force that two surfaces exert on each other when they rub against each other
35
Which direction does friction act?
Opposite of the object, so it causes it to come to a stop
35
Static friction
Acts on objects that aren't moving
36
Sliding friction
occurs when solid surfaces slide over each other
37
Rolling friction
occurs when an object rolls over a surface
38
Fluid friction
Results when an object moves through a fluid - liquid or gas
39
What kind of friction needs the most force to overcome?
The force needed to overcome rolling friction or fluid friction is usually less than sliding friction
40
Free fall
When the force of gravity is an unbalanced force that causes an object to accelerate
41
What is acceleration near Earth's surface due to gravity?
9.8m/s^2
42
What type of fluid friction is objects falling through air?
Air resistance
43
Is air resistance the same for all objects?
No
44
What makes air resistance bigger/smaller?
It increases with surface area and velocity
45
When does the velocity of a falling object stop increasing?
Once all forces are balanced. Air resistance increases until it's equal to the force of gravity
46
Projectile
An object that is thrown.
47
Which way does a projectile move?
Horizontally, the force of gravity pulls it towards Earth
48
Who created the three laws of motion?
The English mathematician Sir Isaac Newton
49
What is the first law of motion?
The law of inertia
50
Inertia
An object's resistance to a change in motion
51
What does the amount of inertia an object has depend on?
The more mass the more inertia there is, because they require a greater force to cause a change in motion
52
What does Newton's second law of motion say?
Acceleration depends on the object's mass and the net force acting on the object
53
What is the acceleration equation?
Acceleration = Net force/mass
54
How is acceleration measured?
Meters per second (m/s^2)
55
How do you increase acceleration?
By increasing the force. They both get larger. Also by decreasing mass
56
Forces are not ____
One-sided
57
What happens when an object exerts a force on another object?
The second object exerts a force back on the first object
58
What are the two forces called?
Action and reaction
59
What does Newton's third law of motion say?
If one object exerts a force on another object, then the second object exerts a force of equal strength in the opposite direction on the first object
60
Can the action and reaction be added together?
No, forces can only be added together if they are acting on the same object

8th and 9th Grade (71 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions