Acar moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the
next 15 minutes. the total distance covered by the car is:
(a) 100 km (b) 25 km (c) 15 km (d) 10 km

Two kilograms of air within a piston–cylinder assembly executes a carnot power cycle with maximum and minimum temperatures of 800 k and 300 k, respectively. the heat transfer to the air during the isothermal expansion is 60 kj. at the end of the isothermal expansion the volume is 0.4 m3. assume the ideal gas model for the air. determine the thermal efficiency, the volume at the beginning of the isothermal expansion, in m3, and the work during the adiabatic expansion, in kj.