Amassless spring is attached to a support at one end and has a 2.0 μc charge glued to the other end. a -4.0 μc charge is slowly brought near. the spring has stretched 1.2 cm when the charges are 2.1 cm apart. what is the spring constant of the spring?

Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?

Velocity is a description of both speed and direction, therefore it - a vector - a force arrow - the same as acceleration - a magnitude

In a good thermo flask the main cause of heat loss is