Physical Science Chapter 3

Question 1

the study of matter and energy and the interactions occurring between them

Answer 1

physics

Question 2

Italian scientist who viewed the universe, the world, and living things as the special creation of God

Answer 2

Galileo Galilei

Question 3

English scientist who formulated the three laws of motion and some of the first detailed investigations into the behavior of light

Answer 3

Sir Isaac Newton

Question 4

the collective term for the branches of physics developed before 1900

Answer 4

classical physics

Question 5

the collective term for the branches of physics developed since 1900

Answer 5

modern physics

Question 6

mathematical quantity that has only a magnitude (size or amount)

Answer 6

scalar quantity (scalar)

Question 7

mathematical quantity that has both magnitude and direction

Answer 7

vector quantity (vector)

Question 8

scalar representing the total length of the object’s path

Answer 8

distance

Question 9

vector representing an object’s change in position

Answer 9

displacement

Question 10

an object undergoing a change in position is said to be in _______

Answer 10

motion

Question 11

the study of motions and forces

Answer 11

dynamics

Question 12

the branch of physics that addresses the effects of forces on matter

Answer 12

mechanics

Question 13

vector that measures the displacement of an object per unit time

Answer 13

velocity

Question 14

speed is _________ (scalar or vector)

Answer 14

scalar

Question 15

velocity is ________ (scalar or vector)

Answer 15

vector

Question 16

distance is ________ (scalar or vector)

Answer 16

scalar

Question 17

displacement is _________ (scalar or vector)

Answer 17

vector

Question 18

any change in velocity

Answer 18

acceleration

Question 19

an acceleration opposite the direction of motion

Answer 19

deceleration

Question 20

the book published by Isaac Newton that explained his findings on gravitation

Answer 20

Principia

Question 21

pushing or pulling action of one object on another

Answer 21

force

Question 22

law stating that the velocity of an object does not change unless the object is acted upon by an external force

Answer 22

first law of motion

Question 23

also called the law of inertia

Answer 23

first law of motion

Question 24

law stating that the force required to accelerate an object at a certain rate equals an object’s mass times the desired acceleration

Answer 24

second law of motion

Question 25

SI unit of force and weight

Answer 25

Newton

Question 26

one Newton equals ________

Answer 26

one kilogram times one meter over second squared

Question 27

the acceleration of an object is __________ to the force applied

Answer 27

directly proportional

Question 28

space relative to which motion is measured

Answer 28

frame of reference

Question 29

a vector showing the result of two or more other vectors

Answer 29

resultant

Question 30

states that for every action there is an equal and opposite reaction

Answer 30

third law of motion

Question 31

the resultant of adding the individual forces on an object through vector addition

Answer 31

net force

Question 32

a diagram that represents an object and the forces on it without considering the causes of the force or the reaction forces exerted by the object

Answer 32

free-body diagram

Question 33

describes the relationship of attraction between two objects affected by gravitational force

Answer 33

law of universal gravitation

Question 34

a constant of proportionality in the universal law of gravitation

Answer 34

gravitational constant

Question 35

precisely determined the value of the gravitational constant

Answer 35

Henry Cavendish

Question 36

the amount of gravitational force exerted on an object by the earth or another celestial body

Answer 36

weight

Question 37

the gravitational force exerted on an object near the surface of the earth or any celestial body

Answer 37

gravity

Question 38

effectively the constant rate at which an object in free fall accelerates

Answer 38

acceleration of gravity

Question 39

the velocity at which the magnitude of drag equals an object’s weight, stopping the object from speeding up

Answer 39

terminal velocity

Question 40

the force that causes an object in circular motion to travel in a curved path rather than a straight line

Answer 40

centripetal force

Question 41

the result of a weight’s attempt to move in a straight line

Answer 41

centrifugal force

Question 42

center seeking force

Answer 42

centripetal force

Question 43

center fleeing force

Answer 43

centrifugal force

Question 44

an object that hangs at a fixed point and swings back and forth because of gravity

Answer 44

pendulum

Question 45

the resistance rising due to an object's motion through a fluid or across a surface

Answer 45

friction

Question 46

two main causes of friction

Answer 46

attraction and repulsion

Question 47

the type of friction that affects sliding objects already in motion

Answer 47

kinetic friction

Question 48

a type of friction that affects stationary objects, preventing them from moving

Answer 48

static friction

Question 49

the transfer of energy from one object to another by a force

Answer 49

work

Question 50

the SI unit of work and energy; equal to the work done in moving an object a distance of 1 m by pushing it with a force of 1 N

Answer 50

Joule

Question 51

the rate of doing work or using energy; work done or energy used per unit time

Answer 51

power

Question 52

the SI unit of power; one joule of work done in one second

Answer 52

watt

Question 53

the F.P.S. unit of power, defined by a horse lifting 550 lb. a distance of 1 ft in 1 s.

Answer 53

horsepower

Question 54

the product of an object’s mass and velocity

Answer 54

momentum

Question 55

the law stating that the overall momentum of a system remains constant unless an external force is applied to it

Answer 55

law of conservation of momentum

Question 56

devices for doing work

Answer 56

machines

Question 57

any of the six basic force-multiplying machines

Answer 57

simple machine

Question 58

simple machines provide these three forms of assistance

Answer 58

1. multiply applied force 2. multiply distance 3. change direction of force

Question 59

force applied to a machine

Answer 59

input

Question 60

force that a machine applies after multiplication of the input

Answer 60

output

Question 61

says that energy can be neither created or destroyed; it can only be transferred and change form

Answer 61

law of conservation of energy

Question 62

the number of times a machine multiplies the input

Answer 62

mechanical advantage (MA)

Question 63

the multiplication of force provided by a machine under ideal conditions

Answer 63

ideal mechanical advantage (IMA)

Question 64

the actual multiplication of force a machine provides under nonideal conditions

Answer 64

actual mechanical advantage (AMA)

Question 65

the ratio of work output to work input in a machine

Answer 65

efficiency

Question 66

a simple machine consisting of a rigid bar or beam resting upon a pivot

Answer 66

lever

Question 67

the pivot upon which the beam of the lever rests

Answer 67

fulcrum

Question 68

the part of the lever from the fulcrum to the input

Answer 68

input arm

Question 69

the part of a lever from the fulcrum to the output

Answer 69

output arm

Question 70

a lever in which the input and output forces are on opposite sides of the fulcrum

Answer 70

class 1 lever

Question 71

a lever in which the fulcrum is at one end of the lever, the input is applied to the other end, and the output is between the input and the fulcrum

Answer 71

class 2 lever

Question 72

a lever in which the fulcrum is at one end of the lever, the output is at the other end, and the input force is applied between the fulcrum and the output (OIF)

Answer 72

class 3 lever

Question 73

a simple machine in which a force is applied to rotate a wheel or axle; basically a circular lever

Answer 73

wheel and axle

Question 74

a simple machine consisting of a wheel over which a rope or cable passes

Answer 74

pulley

Question 75

a pulley that does not move with the load but merely reverses the direction of the input force without multiplying it

Answer 75

fixed pulley

Question 76

a pulley directly attached to a moving load

Answer 76

movable pulley

Question 77

a combination of of one or more fixed and one or more movable pulleys

Answer 77

block and tackle

Question 78

a sloping surface that allows an object to be raised without lifting it straight up

Answer 78

inclined plane

Question 79

a special form of inclined plane that modifies the applied force and directs it to the side

Answer 79

wedge

Question 80

a simple machine resembling an inclined plane wrapped around a rod

Answer 80

screw

Question 81

in a screw, the distance from one of the ridges or threads to the next

Answer 81

pitch