A steam engine delivers `5.4×10^(8)J` of work per minute and services `3.6 × 10^(9)J` of heat per minute from its boiler. What is the efficiency of the engine? How much heat is wasted per minute?

The working substance in a Carnot's heat engine absorbs 5xx10^(6)J of heat from the source and reject 2xx10^(6)J of heat of the sink. Calculate the (i) heat converted into work and (ii) efficiency of the engine.

A person trying to lose weight lifts a 10 kg mass, one thousand times, to a height of 0.5m each time. Assume that the P.E. lost each time the person lowers the mass is dissipated. Fat supplies 3.8xx10^(7) J of energy per kg which is converted to mechanical energy with a 20% efficiency rate. How much fat will the dieter use up?

A steam turbine shovel lifts 10^(3) kg of earth to a height of 3.75 m in 4s. If an engine working at 1.09xx10^(4)W is used, then find how much work is wasted per second and the efficiency of the steam shovel.

A trolley of mass 200 kg moves with a uniform speed of 36 km/h on a frictionless track. A child of mass 20 kg runs on the trolley from one end to the other (10 m away) with a speed of 4 ms^(-1) relative to the trolley in a direction opposite to the its motion, and jumps out of the trolley. What is the final speed of the trolley? How much has the trolley moved from the time the child begins to run?

A river 3m deep and 40m wide is flowing at the rate of 2 mk per hour. How much water will fall into the sea in a minute?

If 4xx10^(-3) J of work is done in moving a particles carrying a charge of 16xx10^(-6) C from inifinity to point P. What will be the potential at a point ?

A geyser heats water flowing at the rate of 3.0 litres per minute from 27^(@) to 77^(@)C . If the geyser operates on a gas burner, what is the rate to consumption of the fuel if its heat of combustion is 4.0xx10^(4)J//g?