A Carnot engine takes 5000 kcal of heat from a reservoir at 727$$^\circ$$C and gives heat to a sink at 127$$^\circ$$C. The work done by the engine is
A 100 g of iron nail is hit by a 1.5 kg hammer striking at a velocity of 60 ms$$-$$1. What will be the rise in the temperature of the nail if one fourth of energy of the hammer goes into heating the nail?
[Specific heat capacity of iron = 0.42 Jg$$-$$1 $$^\circ$$C$$-$$1]
A Carnot engine whose heat sinks at 27$$^\circ$$C, has an efficiency of 25%. By how many degrees should the temperature of the source be changed to increase the efficiency by 100% of the original efficiency?
Two metallic blocks M1 and M2 of same area of cross-section are connected to each other (as shown in figure). If the thermal conductivity of M2 is K then the thermal conductivity of M1 will be :
[Assume steady state heat conduction]