Question

You are in a closed room that has no windows and only one source of light, an overhead incandescent light bulb. Around the room, you notice various objects: a yellow banana, a red apple, and a green cucumber. Which of the following best explains what influences the color and brightness of the banana?

a) Color is a property of each object, independent of any light shining on it. The brightness is only dependent on the brightness of the light bulb.

b) Some of the white light is absorbed by the banana, but the portion of the spectrum that is yellow is reflected from the banana. The brightness also depends on the roughness of the surface of the banana.

c) Color is a property of each object, independent of any light shining on it. The brightness is only dependent on the roughness of the surface of the banana.

d) Some of the white light is absorbed by the banana, but the portion of the spectrum that is yellow is reflected from the banana. The brightness is only dependent on the brightness of the light bulb.

e) The banana only emits light that has wavelengths in the yellow light portion of the visible light spectrum. The brightness is only dependent on the brightness of the light bulb.

Answer 1

Answer(d)

Some of the white light is absorbed by the banana, but the portion of the spectrum that is yellow is reflected from the banana. The brightness is only dependent on the brightness of the light bulb.What these fluorescent whitening agents do is absorb the ultraviolet light and re-emit it as blue light that we can clearly see. This counteracts the yellowing of the white objects and makes them look brighter all the time.The process that causes all this is called fluorescence.