Astronaut is traveling in a space vehicle moving at 0.510c relative to the earth. the astronaut measures her pulse rate at 61.0 beats per minute. signals generated by the astronaut's pulse are radioed to the earth when the vehicle is moving in a direction perpendicular to the line that connects the vehicle with an observer on the earth. (due to vehicle's path there will be no doppler shift in the signal.) what pulse rate does the earth-based observer measure?

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?

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?

It takes a lot of energy to get the temperature of water to increase and eventually boil because water has a high heat.