1. a particle has a velocity equal to 0.25 c and a wavelength of 1.3 x 10^-16 m. Calculate the mass of the particle in kilograms. c=3.0 x 10^8 m/s
2. A photon with an energy of 5.0 x 10^-20 J strikes an electron. All of the photon's energy is converted into kinetic energy of the electron. Calculate the velocity of the electron after the strike, assuming it was at rest before the energy transfer.
3. Calculate the wavelength of a photon traveling at a velocity of 0.01 c (speed of light).