1139 Questions & Blanks

Question 1

When a light ray strikes a surface, it may be ______

Answer 1

transmitted, absorbed, reflected, or a combination of the three

Question 2

Two reasons why household mirrors are back-surfaced

Answer 2

to make the silver last longer

to prevent necessary special attention to the silver

Question 3

A refracted wave will ______

Answer 3

bend and change speed

Question 4

Refraction causes an object under water to appear _______

Answer 4

nearer the surface and closer to the observer

Question 5

A light ray entering a glass pane along the normal will ________

Answer 5

change speed only

Question 6

A light ray traveling through a vacuum will _________

Answer 6

change neither speed nor direction

Question 7

A light ray entering water at a 50degree angle with the normal will ________

Answer 7

change both speed and direction

Question 8

A light ray striking a mirror will ______

Answer 8

change direction only

Question 9

The index of refraction of a certain substance is ___________

Answer 9

inversely proportional to the speed of light in that substance

Question 10

What did Willebrord Snell discover about the relationship between the angle of incidence and the angle of refraction?

Answer 10

(Nr)(sinOr) = (Ni)(sinOi)
N = index of refraction
O = angle of refraction/incidence

Question 11

The common mirage that causes water to appear on the road on a hot day ________

Answer 11

results from refraction of light entering layers air at lower density

Question 12

If sundown is listed in the almanac as 7:45 p.m., what exact time does the sun itself actually drop below the horizon.

Answer 12

7:41

Question 13

The primary colors of light

Answer 13

red green blue

Question 14

A white sheet appears white to our eyes because it

Answer 14

absorbs no light and reflects all colors of light

Question 15

A ____________ results in a shorter focal length.

Answer 15

more sharply curved lens

Question 16

An image is a real image if it can be ________

Answer 16

projected upon a screen

Question 17

The word concave means _____

Answer 17

hollow

Question 18

A __________ cannot be projected upon a screen

Answer 18

virtual image

Question 19

What kind of lens is used to magnify objects?

Answer 19

convex

Question 20

The brightness of an image is related to the ______________ and to the ____________

Answer 20

aperture of the camera

focal length of the lens

Question 21

Many modern cameras focus by changing the ____

Answer 21

focal length of the lens

Question 22

The largest refracting telescope in the world is __________

Answer 22

the Yerkes instrument in Wisconsin

Question 23

Why did God create the sun, moon, and stars?

Answer 23

for signs and seasons, and for days and years

Question 24

How do you calculate the total magnification of a compound microscope?

Answer 24

(magnification of objective)(magnification of eye lens)

Question 25

What causes spherical aberration?

Answer 25

mirrors with spherical surfaces do not bring rays of light to a perfect focus

Question 26

Parabolic reflectors used in automobile headlights ____

Answer 26

reflect all the light rays in the same direction

Question 27

In Galileo Galilei’s hand, the telescope became a ___________

Answer 27

powerful tool for astronomy

Question 28

Two major defects of Galileo’s telescope

Answer 28

chromatic aberration and poor field of view