Ch. 12 vocab

Question 0

What is an SI unit that measures a force?

Answer 0

newton

Question 1

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

Answer 1

force

Question 2

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

Answer 2

net force

Question 3

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

Answer 3

friction

Question 4

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

Answer 4

static friction

Question 5

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

Answer 5

sliding friction

Question 6

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

Answer 6

rolling friction

Question 7

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

Answer 7

fluid friction

Question 8

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

Answer 8

Air resistance

Question 9

What is a force that acts between any two masses?

Answer 9

gravity

Question 10

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

Answer 10

terminal velocity

Question 11

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

Answer 11

projectile motion

Question 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?

Answer 12

Aristotle

Question 13

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

Answer 13

Galileo

Question 14

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

Answer 14

Newton

Question 15

How can a force accelerate a moving object?

Answer 15

by changing its speed and direction

Question 16

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

Answer 16

1 km/s2

Question 17

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

Answer 17

add

Question 18

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

Answer 18

subtract

Question 19

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

Answer 19

0

Question 20

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

Answer 20

motion

Question 21

All moving objects are subject to ________.

Answer 21

friction

Question 22

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

Answer 22

fluid friction,
rolling friction,
sliding friction,
static friction

Question 23

A _______ force balances out a downwards force of gravity.

Answer 23

upward

Question 24

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

Answer 24

gravity,

air resistance

Question 25

State Newtons 1st law of motion.

Answer 25

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

Question 26

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

Answer 26

law of inertia

Question 27

State Newton’s second law of motion.

Answer 27

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

Question 28

State Newton’s third law of motion.

Answer 28

For every action, there is an equal but opposite reaction