Find the moments mx and my and the center of mass of the system, assuming that the particles have equal mass m.

four particles are located at points (1,3), (2,3), (3,1), (4,1)

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

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?

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2