chapter 4

Question 1

motion

Answer 1

an objects change in position relative to a reference point

Question 2

speed

Answer 2

the distance traveled divided by the time interval during which the motion occured

Question 3

velocity

Answer 3

the speed of an object in a particular direction

Question 4

acceleration

Answer 4

the rate at which velocity changes over time; an object accelerates if its speed,direction,or both change

Question 5

force

Answer 5

a push or pull an object in order to change the motion of the object; force has size and direction

Question 6

newton

Answer 6

the SI unit for force

Question 7

net force

Answer 7

the combination of all of the forces actiong on an object

Question 8

friction

Answer 8

a force that opposes motion between two surfaces that are in contact

Question 9

gravity

Answer 9

a force of attraction between objects that is due to their masses

Question 10

weight

Answer 10

a measure of the gravitational force exerted on an object; its value can change with the location of the object in the universe.

Question 11

mass

Answer 11

a measure of the amount of matter in an object.