Chapter 16, Problem 65A

(a)

To determine

To give reason − red cellophane look red in reflected light.

Explanation of Solution

Introduction:

It is very well known that any objects can be seen merely in the presence of light. The light rays’ incident on an object gets reflected from the surface of that object and it is responsible for the visibility of that object. An object reflects the light of its own color and absorbs all the other colors in an incident light. Hence, the color of the light reflected from an object is the actual color of that object.

Red cellophane look red in reflected light because it reflects red color. Red, Blue, and Green are the three basic colors. The combination of these three colors with appropriate intensity makes the white light. Thus the cellophane reflects red color means it absorbs blue and green color of the light incident on it.

(b)

To determine

To give reason − red cellophane make a white light bulb look red when the cellophane is held between our eye and the light bulb.

Answer to Problem 65A

Because red light is transmitted through the red cellophane.

Explanation of Solution

The white light is a mixture of all the colors in the light spectrum of visible region. When the white light is made to incident on an object, all the wavelengths except a particular wavelength of its color get absorbed from an object. When red cellophane is held between a white light and an observer’s eye, the bulb looks redbecause the red cellophane allows red light to transmit through it by absorbing all other wavelengths of white light.

(c)

To determine

To explain: The effect on the blue and green light.

Answer to Problem 65A

The blue and green lights get absorbed by the red cellophane.

Explanation of Solution

The white light is a mixture of all the colors in the light spectrum of visible region. When the white light is made to incident on an object, all the wavelengths except a particular wavelength of its color are gets absorbed from an object. When red cellophane is held in front of a white light, the red cellophane allows red light to transmit through it by absorbing all other wavelengths of white light. Thus,the blue and green lights get absorbed by the red cellophane.