91影视

Why don鈥檛 we feel the momentum of sunlight when we are on the beach?

Integrated Concepts An electron microscope produces electrons with a 2.00-pm wavelength. If these are passed through a 1.00-nm single slit, at what angle will the first diffraction minimum be found?

Is the photoelectric effect a direct consequence of the wave character of EM radiation or of the particle character of EM radiation? Explain briefly.

What aspect of the blackbody spectrum forced Planck to propose quantization of energy levels in its atoms and molecules?

(a) If the position of a chlorine ion in a membrane is measured to an accuracy of \(1.00 \mu \mathrm{m}\), what is its minimum uncertainty in velocity, given its mass is \(5.86 \times 10^{-26} \mathrm{~kg} ?\) (b) If the ion has this velocity, what is its kinetic energy in \(\mathrm{eV}\), and how does this compare with typical molecular binding energies?

Tanning salons use 鈥渟afe鈥� UV with a longer wavelength than some of the UV in sunlight. This 鈥渟afe鈥� UV has enough photon energy to trigger the tanning mechanism. Is it likely to be able to cause cell damage and induce cancer with prolonged exposure?

(a) Find the momentum of a 4.00-cm-wavelength microwave photon. (b) Discuss why you expect the answer to (a) to be very small.

(a) What is the momentum of a 0.0100-nm-wavelength photon that could detect details of an atom? (b) What is its energy in MeV?

If you pick up and shake a piece of metal that has electrons in it free to move as a current, no electrons fall out. Yet if you heat the metal, electrons can be boiled off. Explain both of these facts as they relate to the amount and distribution of energy involved with shaking the object as compared with heating it.

At what velocity does a proton have a 6.00-fm wavelength (about the size of a nucleus)? Assume the proton is nonrelativistic. \(\left(1\right.\) femtometer \(\left.=10^{-15} \mathrm{~m} .\right)\)