A boy of mass 45 kg and his dog of mass 25 kg stand on a diving board. If the boy stands 2.0 meters from the pivot of the
board, and the dog stands 1.2 meters from the pivot, what is
the net torque on the board? Use g = 9.8 m/s2.

How have the competing explanations' experiments on atoms affected the development of the atomic model?

Acylinder with a movable piston contains 11.7 moles of a monatomic ideal gas at a pressure of 1.32×10^5 pa. the gas is initially at a temperature of 300 k. an electric heater adds 43200 j of energy into the gas while the piston moves in such a way that the pressure remains constant. cp=20.79 j k^−1 mol^−1 for a monatomic ideal gas, and that the number of gas molecules is equal to avogadro's number (6.022×10^23) times the number of moles of the gas. (a) what is the temperature of the gas after the energy is added? (b) what is the change in volume of the gas? (c) how much work is done by the gas during this process?

=force × distance a. work b. velocity c. pressure d. momentum