Photoelectric Effect and Photon Energy

Dan the Tudor explains the photoelectric effect, covering key equations and concepts. He provides examples on calculating cutoff frequency, kinetic energy, and work function. The video includes detailed problem-solving steps, emphasizing the relationship between light frequency, energy, and electron ejection.

What is the main factor that determines whether light can eject an electron from a metal surface?

• The temperature of the metal

• The color of the light

• The angle of incidence

• The energy of the light

Which equation is used to calculate the energy of a photon?

• E = hf

• E = mv^2

• E = mc^2

• E = qV

What is the cutoff frequency?

• The minimum frequency needed to eject an electron

• The frequency at which light changes color

• The frequency at which light is absorbed

• The maximum frequency a metal can reflect

How is the cutoff frequency related to the work function?

• It is directly proportional to the work function

• It is inversely proportional to the work function

• It is equal to the work function

• It is unrelated to the work function

What is the first step in calculating the kinetic energy of an ejected electron when given the wavelength of light?

• Determine the work function

• Find the speed of light

• Measure the electron's mass

• Calculate the frequency of the light

Which constant is used to calculate the energy of a photon?

• Coulomb's constant

• Boltzmann constant

• Planck's constant

• Gravitational constant

What is the mass of an electron used in kinetic energy calculations?

• 9.11 x 10^-31 kg

• 1.67 x 10^-27 kg

• 1.60 x 10^-19 kg

• 6.63 x 10^-34 kg

How do you convert energy from electron volts to joules?

• Multiply by 6.63 x 10^-34

• Multiply by 1.6 x 10^-19

• Divide by 6.63 x 10^-34

• Divide by 1.6 x 10^-19

What is the work function of a metal if the kinetic energy of ejected electrons is 1.62 x 10^-19 J and the photon energy is 2.85 x 10^-19 J?

• 2.23 x 10^-19 J

• 1.23 x 10^-19 J

• 4.23 x 10^-19 J

• 3.23 x 10^-19 J

What is the significance of the work function in the photoelectric effect?

• It is the speed at which electrons are ejected

• It is the wavelength of the incident light

• It determines the color of the emitted light

• It is the energy required to remove an electron from a metal