Question 1

The walls of a blackbody cavity are at a temperature of 27° C. What is the frequency of the radiation of maximum intensity?

Question 2

Assume that a 100 – W light bulb gives off 2.50% of its energy as visible light. How many photons of visible light are given off in 1.00 min? (Use an average visible wavelength of 550 nm)

Question 3

What is the energy of photons (joules) emitted by a 107.5 MHz FM radio station?

Question 4

What is the longest wavelength of light that will emit electrons from a metal whose work function is 3.50 eV?

Question 5

A metal with a work function of 2.40 eV is illuminated by a beam of monochromatic light. If the stopping potential is 2.5V, what is the wavelength of the light?

Question 6

What is the de Broglie wavelength of a 1000 kg car moving at a velocity of 25 m/s?

Question 7

A hydrogen atom in its ground state is excited to the n=5 level. It then makes a transition directly to the n=2 level before returning to its ground state.

a)What are the wavelengths of the emitted photons?

b)Would any of the emitted wavelengths be in the visible region?