10 advance exam 1

A ray of light travels in a __________.

• circle

• back-and-forth motion

• curved line

• straight line

Danish astronomer Ole Roemer first measured the speed of light by studying __________.

• how lasers travel in space

• how light traveled around two mountains

• the Moon

• the orbit of Io, a moon of Jupiter

.In the figure below, the luminous intensity from the lamp on the screen and the luminous intensity from the candle on the screen are the same. If the candle were moved so that it was d/2 to the right of the screen, but the lamp was not moved, how would the luminous intensity of the lamp have to be adjusted to make each side of the screen equally illuminated?

• It would need to be quartered.

• It would need to be halved.

• It would need to be doubled.

• It would need to be quadrupled.

· The two main factors affecting the illuminance of an object are __________.

A.

B.

C.

D.

• distance and brightness

• hardness and color

• distance and hardness

• color and brightness

· .__________ is the rate at which visible light is emitted from an object.

• Luminous flux

• Frequency flux

• Illuminated flux

• Amplitude fluxB.

· In the figure below, if r is decreased to 0.25 m, what will be the illuminance of the sphere?

• 2224 lx

• 556 lx

• 139 lx

• 8.69 lx

· Illuminance __________ as the light source moves away from the object.

• decreases with an inverse relationship

• decreases with an inverse square relationship

• increases with an inverse square relationship

• increases with an inverse relationship

· In the figure below, if r is decreased to 0.25 m, what will be the total luminous flux striking the inside of the sphere?

• 1750 lm

• 7000 lm

• 438 lm

• 875 lm

· In the figure below, the luminous intensity from the lamp on the screen and the luminous intensity from the candle on the screen are the same. If the candle were moved so that it was 2d to the right of the screen, but the lamp was not moved, how would the luminous intensity of the lamp have to be adjusted to make each side of the screen equally illuminated?

• It would need to be halved.

• It would need to be quartered.

• It would need to be quadrupled.

• It would need to be doubled

· What did Roemer demonstrate?

• light travels instantaneously

• the correct speed of light

• light has no speed

• light travels at a finite speed