Einstein's Photoelectric Effect Concepts

The video explores the photoelectric effect, starting with Hertz's experiment in 1887, which showed that certain metals conduct electricity when exposed to light. This phenomenon, known as the photoelectric effect, could not be explained by wave theory. Einstein used Max Planck's theory of electromagnetic radiation to explain it, proposing that light consists of particles called photons. He demonstrated that the energy of these photons must exceed a threshold frequency to eject electrons from a metal surface, leading to his Nobel Prize.

What was the main purpose of Hertz's experiment conducted in 1887?

• To measure the speed of light in different media

• To demonstrate the wave nature of light

• To show that metals can conduct electricity in a vacuum

• To investigate the effect of light on metal surfaces

Which metals were found to conduct electricity in the presence of light during the photoelectric effect?

• Iron and Copper

• Gold and Silver

• Potassium and Cesium

• Aluminum and Zinc

What is the threshold frequency in the context of the photoelectric effect?

• The frequency at which light changes color

• The minimum frequency required to observe the effect

• The maximum frequency at which electrons are ejected

• The frequency at which light intensity is highest

Why was the wave theory of light unable to explain the photoelectric effect?

• It did not account for the existence of photons

• It suggested that light intensity should affect electron energy

• It predicted that light could not eject electrons

• It only applied to visible light

What did Einstein propose about the nature of light to explain the photoelectric effect?

• Light is a continuous wave

• Light is composed of particles called photons

• Light is a form of sound

• Light is a chemical reaction

According to Einstein, what determines the kinetic energy of ejected electrons?

• The duration of light exposure

• The color of the light

• The frequency of the light

• The intensity of the light

What is the relationship between photon energy and the threshold frequency in Einstein's explanation?

• Photon energy must be less than the threshold frequency

• Photon energy must be equal to the threshold frequency

• Photon energy must be greater than the threshold frequency

• Photon energy is unrelated to the threshold frequency

What is the formula Einstein used to describe the photoelectric effect?

• E = mv^2

• E = hν - hν₀

• E = hf + c

• E = mc^2

In Einstein's formula, what does 'hν₀' represent?

• The kinetic energy of the electron

• The work function of the metal

• The speed of light

• The intensity of the light

What did Einstein's explanation of the photoelectric effect contribute to physics?

• It confirmed the wave theory of light

• It introduced the concept of photons

• It disproved the existence of electrons

• It showed that light has no effect on metals