A70 kilogram mountaineer is standing on the summit of mt. everest. the distance between the mountaineer and the center of earth is 6.39 × 106 meters. what is the magnitude of the force of gravity acting on the mountaineer? (the value of g is 6.673 × 10-11 newton meter2/kilogram2. the mass of earth is 5.98 × 1024 kilograms.)

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.