Exploring Physics Chapters 8-10

Question 1

The bending of the sun’s rays at sunset is an example of

Answer 1

refraction.

Question 2

The frequency of a sound is known as its

Answer 2

pitch

Question 3

How many decibels is ordinary conversation?

Answer 3

50-60

Question 4

If pitch increases, then source and observer must be moving ___ one another.

Answer 4

toward

Question 5

How many decibels is the average home sounds such as the humming of a refrigerator?

Answer 5

20-30

Question 6

As sound waves spread out, they grow weaker by the ___ of the distance.

Answer 6

square

Question 7

is a surface of light sensitive nerves.

Answer 7

retina

Question 8

The eye has cones that can detect red, green, and ___ light.

Answer 8

blue

Question 9

The pitch of a string on a stringed instrument depends on the length, thickness, and _______________ of the string.

Answer 9

tension

Question 10

The frequency of light is its

Answer 10

color.

Question 11

The study of sound is known as

Answer 11

acoustics

Question 12

Sound waves travel at the ___ in air depending on their source.

Answer 12

same speed

Question 13

is the opening through which light enters the eye.

Answer 13

pupil

Question 14

Coulomb’s law of static electric force is very similar to Newton’s law of gravity, but with ___ replacing mass.

Answer 14

charge

Question 15

Thales of Melitus discovered that ___ could be given a charge of static electricity.

Answer 15

amber

Question 16

The image behind a flat mirror is a (A. real, B. virtual) image.

Answer 16

virtual

Question 17

The speed of light is ___ in water than in air.

Answer 17

slower

Question 18

carries information from the eye to the brain.

Answer 18

optic nerve

Question 19

The ohm is a unit for measuring

Answer 19

resistance

Question 20

To reduce the heating effect of electricity in wires, the current is reduced but the ___ is increased.

Answer 20

voltage

Question 21

is sensitive to light and can distinguish color.

Answer 21

cones

Question 22

An object with a ___ charge has more protons than electrons.

Answer 22

positive

Question 23

Which moves more freely, an electron or proton?

Answer 23

electron

Question 24

How many decibels is the rustling of leaves?

Answer 24

8

Question 25

State Ohm’s law

Answer 25

current = voltage/resistance, or in words: current is directly proportional to voltage and inversely proportional to resistance.

Question 26

High frequency, ultrasonic sounds reflect ___ from small objects than low frequency sounds.

Answer 26

better

Question 27

adjusts light to the best focus.

Answer 27

lens

Question 28

The ___ pitch an object can make is known as its natural or fundamental frequency.

Answer 28

lowest

Question 29

How many decibels is a whisper?

Answer 29

10-20

Question 30

How many decibels is an automobile

Answer 30

40-50

Question 31

The force that pushes electrons around a circuit is

Answer 31

voltage

Question 32

Do all metals conduct electricity?

Answer 32

yes

Question 33

The three properties of a sound are frequency, intensity, and ___.

Answer 33

quality

Question 34

controls the amount of light that enters the eye.

Answer 34

iris

Question 35

List two examples of a practical use found for battery-powered vehicles?

Answer 35

golf carts and hybrid cars

Question 36

How many decibels is thunder?

Answer 36

110

Question 37

Sunlight is a mixture of all the colors of the

Answer 37

rainbow.

Question 38

Which is stronger, electrostatic or gravity?

Answer 38

electrostatic

Question 39

The distance along a wave, including crest and trough, is its

Answer 39

wavelength

Question 40

How many decibels is heavy street traffic?

Answer 40

70-80

Question 41

The observation that light bounces from a mirror at the same angle at which it enters is known as the law of

Answer 41

reflection.

Question 42

Most modern large telescopes use a ___ to collect light and bring it to a focus.

Answer 42

mirror

Question 43

A lens thicker in the middle than at the edges is

Answer 43

convex.

Question 44

The loudness of sound is measured in

Answer 44

decibels

Question 45

brings light to a focus.

Answer 45

cornea

Question 46

Glass is an example of a

Answer 46

nonconductor

Question 47

How many decibels is a jack hammer?

Answer 47

90-100

Question 48

is sensitive to light but cannot see color.

Answer 48

rods