if you place a paperclip below a beaker, and pour water into the beaker...?

Question

if you place a paperclip below a beaker, and pour water into the beaker why can't the paperclip be seen from the side of the beaker?

Answer 1

This phenomenon is due to the principles of refraction and total internal reflection. Refraction is the cause of heat haze, and of the dappled light at the bottom of a shallow pool. It helps makes diamonds sparkle and plays a part in rainbows.

What your expirement demonstrates are the principles of refraction and total internal reflection. In explaination, the light from the paper clip is being refracted as it enters the bottom of the beaker. When it hits the side of the beaker it strikes at such an angle that it undergoes total internal reflection and can only exit the water at the top surface. The paper clip seems to disappear! This is really the principle of fiber optics. Light enters one end of the fiber and can only exit at the other end.

Answer 2

It depends on the form of the baker. When the angle between the normal (the perpendicular to the bottom of the baker ) and the light ray is greater than sin-1 0.75 49°, you have the phenomenon of total reflection and the ray can not escape out of the beaker