A girl is sledding down a slope that is inclined at 30° with respect to the horizontal. The wind is aiding the motion by providing a steady force of 131 N that is parallel to the motion of the sled. The combined mass of the girl and the sled is 73.1 kg, and the
coefficient of kinetic friction between the snow and the runners of the sled is 0.189. How much time is required for the sled to travel
down a 130-m slope, starting from rest?

Steam is generated in a boiler of a cogeneration plant at 10 mpa and 450°c at a steady rate of 5 kg/s. in normal operation, steam expands in a turbine to a pressure of 0.5 mpa and is then routed to the process heater, where it supplies the process heat. steam leaves the process heater as a saturated liquid and is pumped to the boiler pressure. in this mode, no steam passes through a condenser, which operates at 20 kpa. (a) determine the power produced in the turbine and the rate at which process heat is supplied in this mode. (b) determine the power produced in the turbine and the rate of process heat supplied if only 60 percent of the steam is routed to the process heater and the remainder is expanded to the condenser pressure. (3.32 mw; 9.69 mw; 4.25 mw; 5.82 mw)

For which pair of objects would adding the same a

Física: un futbolista patea hacia el arco con una velocidad de 15m/ah, calcular: a)el alcance para un ángulo de tiro de 25º, b) el tiempo que el balón permanece en el aire.