Reference no: EM132600154

1. What is the surface temperature of Betelgeuse, a red giant star in the constellation of Orion, which radiates with a peak wavelength of about 970 nm?

2. Rigel, a bluish-white star in Orion, radiates with a peak wavelength of 145 nm. Find the temperature of Rigel's surface.

3. When light of wavel.ength 150 nm falls on a lithium surface, electrons having a maximum kinetic energy of 5.98 eV are emitted Find values for the following.

a. the work function of lithium (eV)

b. the cutoff wavelength (nm)

c. the frequency corresponding to the cutoff wavelength (Hz)

4. The extremes of the x-ray portion of the electromagnetic spectrum range from λ ≈ 1.00 ? 10-9 m to λ ≈ 1.00 ? 10-11 m. Find the minimum accelerating voltages required to produce wavelengths at these two extremes.

For 1.00 ? 10-9 m, V =

For 1.00 ? 10-11 m, V =

5. When x-rays of wavelength of 0.129 nm are incident on the surface of a crystal having a structure similar to that of NaCl, a first-order maximum is observed at 8.15°. Calculate the interplanar spacing based on this information.