A rat is placed in an environment where the floor gives the rat small electric shocks. The only way to get rid of the shocks is to press a lever in the corner of the box. The rat quickly learns to press the lever. This is an example of

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)