In Fig. 6-46, a box of ant aunts (total mass m1 = 1.65 kg) and a box of ant uncles (total mass m2 = 3.30 kg) slide down an inclined plane while attached by a massless rod parallel to the plane. The angle of incline is 8 = 30.0. The coefficient of kinetic friction between the aunt box and the incline is f.Ll = 0.226; that between the uncle box and the incline is Jk2 = 0.113. Compute (a) the tension in the rod and (b) the magnitude of the common acceleration Fig. 6-46 60. of the two boxes. (c) How would the answers to (a) and (b) change if the uncles trailed the aunts?
Chapter 30: Quantum Physics The “ideal” blackbody absorbs all the light that is incident upon it and is an ideal radiator The distribution of energy in blackbody radiation is independent of the material from which the blackbody is constructed — it depends only on the temperature, T Classical predictions were that the intensity increased rapidly with frequency, hence the ultraviolet catastrophe. Planck’s constant is a very tiny number; this means that the quantization of the energy of blackbody radiation is imperceptible in most macroscopic situations A more intense beam of light will contain more photons, but the energy of each photon does not change The photoelectric effect occurs when a beam of light strikes a metal