Ch. 12 vocab Flashcards Preview

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Flashcards in Ch. 12 vocab Deck (29):
0

What is a push or pull that acts over an object?

force

1

What is an SI unit that measures a force?

newton

2

What is the overall force acting on an object after all the forces are combined?

net force

3

What is a force that opposes the motion of objects that touch as they move past each other ?

friction

4

What is the friction force that acts on objects that are not moving?

static friction

5

What is a force that opposes the direction of motion of an object as it slides over a surface?

sliding friction

6

What is a change in shape at the point of rolling contact?

rolling friction

7

What is a force that opposes the motion of an object through a fluid?

fluid friction

8

What is it called when fluid friction acts on an object moving through the air?

Air resistance

9

What is a force that acts between any two masses?

gravity

10

What is the constant velocity of a falling object when the force of air resistance equals the force of gravity?

terminal velocity

11

What is the motion of a falling object after it is given an initial forward velocity?

projectile motion

12

Who was an ancient Greek scientist and philosopher who incorrectly proposed that a force is required to keep an object moving at a constant?

Aristotle

13

Who was an Italian scientist who concluded that moving objects not subjected to friction or an other force would continue to move indefinitely?

Galileo

14

Who was the first person to define mass and mass and force?

Newton

15

How can a force accelerate a moving object?

by changing its speed and direction

16

A newton causes a 1km mass to accelerate to what?

1 km/s2

17

If forces are moving in the same direction, you ______ the forces.

add

18

If forces are moving in the opposite direction, you _________ the forces.

subtract

19

If the net force is ____, then there is no motion.

0

20

When an unbalanced force acts on an object, there is _________.

motion

21

All moving objects are subject to ________.

friction

22

List the order of the four frictions in order from weakest to strongest.

fluid friction,
rolling friction,
sliding friction,
static friction

23

A _______ force balances out a downwards force of gravity.

upward

24

_________ causes objects to accelerate downwards, whereas ___ __________ acts in the direction opposite to the motion and reduces acceleration.

gravity,
air resistance

25

State Newtons 1st law of motion.

An object at rest tends to stay at rest, while an object in motion tends to stay in motion unless acted upon by an unbalanced force

26

What is Newton's first law of motion also known as?

law of inertia

27

State Newton's second law of motion.

Acceleration is directly proportional to the size of the force
Acceleration is inversely proportional to mass
A=f/m

28

State Newton's third law of motion.

For every action, there is an equal but opposite reaction