pays ch 4 quiz

Question 1

an object moves with constant velocity when…

Answer 1

no net force is is exerted on it

Question 2

Newton’s first law

Answer 2

every object continues is its state of rest or uniform velocity in a straight line as long as no net force acts on it

Question 3

inertia

Answer 3

tendency of an object to maintain its state of rest/uniform velocity in a straight line

Question 4

in what frame does Newton’s first law not hold?

Answer 4

in accelerating reference frames

Question 5

measure of the inertia of an object

Answer 5

mass

Question 6

the more mass an object has, the greater the _____ needed to give it a particular acceleration

Answer 6

force

Question 7

weight

Answer 7

pull of gravity acting on an object

Question 8

a ____ causes acceleration

Answer 8

net force

Question 9

the acceleration of an object is directly proportional to the

Answer 9

net applied force (and depends on mass)

Question 10

newton’s 2nd law

Answer 10

the acceleration of an object is directly proportional to the net force acting on it, and is inversely proportional to the object’s mass. the direction of the acceleration is in the direction of the net force acting on the object.

Question 11

newton’s 2nd law as an equation

Answer 11

a=net force/mass

Question 12

net force =

Answer 12

(m)(a)

Question 13

an action capable of accelerating an object

Answer 13

force

Question 14

F is a vector, so F=ma can be written in

Answer 14

any inertial reference frame

Question 15

1 N =

Answer 15

(1kg)(1m/s^2)

Question 16

mass in force problems must be in

Answer 16

kg

Question 17

newton’s 3rd law

Answer 17

whenever one object exerts a force on a second object, the second object exerts an equal force in the opposite direction on the first

Question 18

the “action” force and “reaction” force are acting on ____ objects

Answer 18

different

Question 19

the force exerted on the person by the ground (Fpg) =

Answer 19

= - the force exerted in the ground by the person (-Fgp)

Question 20

a is the acceleration of one particular object, and the net force must include only

Answer 20

forces on that one object

Question 21

gravitational force (Fg) =

Answer 21

=mg

Question 22

the magnitude of the force of gravity on an object is called the object’s

Answer 22

weight

Question 23

when a contact force acts perpendicular to the common surface of contact, it is referred to as the

Answer 23

normal force (Fn)

Question 24

Fg and Fn are

Answer 24

equal magnitude and opposite directions

Question 25

the normal force is/is not always equal to the weight

Answer 25

is not

Question 26

sliding friction

Answer 26

kinetic friction

Question 27

the magnitude of the force of kinetic friction depends on

Answer 27

the nature of the two sliding surfaces

Question 28

the force of kinetic energy acts ____ to the direction of the objects velocity

Answer 28

opppsite

Question 29

static friction

Answer 29

force parallel to the two surfaces that can arise even when they are not sliding

Question 30

what happens when you exceed the maximum force of static friction

Answer 30

object starts moving, kinetic force takes over

Question 31

it is easier to keep a heavy object sliding than it is to start it in the first place, which is consistent with the coefficient of static friction being ____ than the coefficient of kinetic friction.

Answer 31

greater