Introducing Photoelectric Effect

1. What is the electromagnetic spectrum?

• A) A measure of how fast light travels

• B) A range of light wavelengths from gamma rays to radio waves

• C) The theory of light waves

• D) A tool to detect radio waves only

2. What type of light can humans detect with their eyes?

• A) Ultraviolet light

• B) Infrared ligh

• C) Visible light

• D) Gamma rays

3. What was the main limitation of the wave theory of light?

• A) It couldn’t explain the photoelectric effect.

• B) It couldn’t explain the speed of ligh

• C) It couldn’t explain the electromagnetic spectrum.

• D) It was unable to explain the behavior of radio waves.

4. What is the photoelectric effect?

• A) The observation that light can travel through solid objects

• B) The process by which light is absorbed by a metal plate

• C) The ejection of an electron from a metal plate when irradiated with light

• D) The bending of light when it passes through different materials

5. According to the video, what does the ability of light to eject an electron depend on?

• A) The intensity of the light

• B) The speed of the light

• C) The temperature of the light

• D) The frequency (colour) of the light

6. What did Albert Einstein propose to explain the photoelectric effect?

• A) That light behaves only as a wave

• B) That light is made of quanta, or photons

• C) That light’s intensity is the main factor in ejecting electrons

• D) That energy is continuous, not quantized

7. An electron​ is ejected when struck by a _____ (1) with enough ​ ______ (2). If the photons don’t have _______(3) energy, no electron will be ejected.

• A, photon, energy, sufficient

• B, light, energy, sufficient

• C, photon, energy, kinetic

• D, proton, energy, enough

8. What theory explains that light behaves both as a particle and a wave?

• A) The theory of relativity

• B) The wave theory of light

• C) Wave-particle duality

• D) Newtonian mechanics