Einstein and the Photoelectric Effect

The video explains the dual nature of light, demonstrating the photoelectric effect using a zinc plate and electroscope. It shows how UV light can discharge the electroscope by releasing electrons, unlike visible light. This phenomenon supports the particle model of light, where light is seen as packets of energy or photons. Albert Einstein's explanation of this effect earned him the Nobel Prize in 1921.

What is one of the fundamental ideas in physics regarding the behavior of light?

• Light behaves only as a wave.

• Light behaves only as a particle.

• Light can behave as both waves and particles.

• Light does not interact with matter.

Why is it necessary to scrub the zinc plate with iron wool before the demonstration?

• To remove a surface oxide layer.

• To change its color.

• To charge it positively.

• To make it shiny.

What method is used to charge the zinc plate negatively?

• Charging by radiation.

• Charging by induction.

• Charging by friction.

• Charging by conduction.

What happens when visible light is shone on the negatively charged zinc plate?

• The plate changes color.

• Nothing happens.

• The gold leaf falls.

• The gold leaf rises.

What is observed when ultraviolet light is shone on the zinc plate?

• The gold leaf rises.

• The gold leaf falls.

• The plate emits sound.

• Nothing happens.

Why can't the wave model of light explain the photoelectric effect?

• Because it doesn't account for light's speed.

• Because it doesn't consider light's color.

• Because it doesn't explain light's energy packets.

• Because it doesn't involve light's direction.

What term is used to describe the packets of energy that light consists of?

• Waves

• Atoms

• Particles

• Quanta or photons

Why can't a single photon of visible light release an electron from the zinc plate?

• It has less energy than needed.

• It has too much energy.

• It is too fast.

• It is too large.

What major scientific contribution did Albert Einstein make regarding the photoelectric effect?

• He explained the photoelectric effect using photons.

• He invented the electroscope.

• He developed the wave model of light.

• He discovered the electron.

For what work was Albert Einstein awarded the Nobel Prize in 1921?

• His invention of the light bulb.

• His discovery of the electron.

• His work on the photoelectric effect.

• His work on relativity.