A 10cm diameter and 1m long torsion bar (spring) is made of a material with a shear elastic modulus (G) of 30GPa and a Yield strength (Sy) of 200MPa. If maximum stress allowed in the bar is limited to 75% of its Yield strength, what is the maximum amount of potential energy that can be stored in this spring (in N-m)?

Acarnot refrigerator operates in a room in which the temperature is 21°c and of power when operating. if the food compartment of the refrigerator is consumes 3 kw to be maintained at 2°c, determine (a) the coefficient of performance of the cycle and (b) the rate of heat removal from the food compartment. refrigerator cycle that has a higher coefficient of performance than that of the discussed (e) is it possible to develop a carn ot refrigerator, operating between the same temperature limits? explain