Aball having a mass of 0.20 kilograms is placed at a height of 3.25 meters. if it is dropped from this height, what will be the kinetic energy of the ball when it reaches 1.5 meters above the ground?

The atoms in a nickel crystal vibrate as harmonic oscillators with an angular frequency of 2.3 × 1013 rad/s. the mass of a nickel atom is 9.75 × 10-26 kg. what is the difference in energy between adjacent vibrational energy levels of nickel? (h = 6.626 × 10-34 j • s, , 1 ev = 1.60 × 10-19 j)