The proton with initial v1 = 3.00 x 10^5 m/s enters a region 1.00 cm long where it is accelerated. its final velocity is v = 6.40 x 10^6 m/s . what was its constant acceleration. answer in 10^15 m/s^2

Photoelectrons with a maximum speed of 6.50 x 107 m/s are ejected from a surface in the presence of light with a frequency of 6.75 x 1014hz. if the mass of an electron is 9.10 x 10-31 kg, calculate in joules the maximum kinetic energy of a single electron. 3.84 x 10-15 j 1.92 x 10-15 j 5.92 x 10-23 j 3.07 x 10-16 j