Physics Light and Color Test: Multiple Choice

Going into a less dense medium (large n to small n), light bends _____ the normal.

Away from

What are the units for luminous intensity?

Candela

The incident angle that causes the refracted ray to lie along the boundary between two media is called _____.

Critical angle

What causes a rainbow?

Dispersion

The speed of light can be found by which of the following?

Distance/time, frequency * wavelength

What symbol is used for illumination?

E

Light is a(n) _____ wave.

Electromagnetic

Does a luminous body reflect or emit light waves?

Emit

What symbol is used for luminous intensity?

I

Which quantity varies inversely with the square of the distance from a light source?

Illuminance

The ratio of the speed of light in a vacuum to its speed in a material is called _____.

Index of refraction

Which of the following describes an electromagnetic wave that the human eye can detect?

Light

The rate at which light is emitted from a source is called _____.

Luminous flux

What are the units for illumination?

Lux

Which type of objects do not transmit light?

Opaque

What symbol is used for luminous flux?

P

A straight line that represents the path of a light beam is called a(n) _____.

Ray

What color has a wavelength of 700 nm?

Red

Does an illuminated body emit or reflect light waves?

Reflect

Does light travel slower or faster in the earth's atmosphere than in outer space?

Slower

The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant describes _____.

Snell's law

In a mirage, the index of refraction for air changes as the _____ changes (causing the light rays to bend).

Temperature

Which type of objects transmit light but distort its path?

Translucent

Which type of objects transmit light without distorting the direction of light rays?

Transparent

What symbol is used for the speed of light?

c

What is the formula for the index of refraction?

n = c/v

To find the critical angle, you would take the inverse sin of _____.

nr/ni

If an object is moved three times as far from a flashlight, the illumination of that object will be _____ its original value.

1/9

What is the wavelength of violet light?

400 nm

What is the index of refraction of air?

1.00