Can you explain how will you demonstrate to a friend that: (about physics)?

Question

a. light travels in a straight line in a given medium

b. white light is made up of different colors

help me...

Answer 1

well, if you don't have a prism lying around,

a. Shine a flash light against a wall. Notice the full circle it makes. Then put something to block the light. You will see that the shadow takes the shape of the object blocking the light. The light does not move around the object to complete the light circle.

b. Find a tube tv (not lcd or plasma). Make the tv project a white image. If you go close to the tv (like almost pressing your face to the glass) you will see that the image is made up of many colors. Don't do this too often, as this is probably bad for your eyes.

Answer 2

b.  You can use a prism.

a.  I may be wrong, but I thought that the path of light was affected by gravity.

Answer 3

Shadows are a good way to show light travels in a straight line.

To show white light is made of different colors, just use a CD, the bits on it have a spacing that will separate out the colors of the light, or just turn off all lights and shine a flashlight on different objects.  The different colors in the white light will get absorbed and reflected.

Answer 4

Shine a light through a prism!

It demonstrates both of those properties.

The light (white light) will bend and break apart into the different frequencies and show a "rainbow" of colors.