The object with a mass of 1kg begins to slide from rest along a smooth slope with an inclination of 37 degrees. When it slides for 4S, the gravity will drop An object with a mass of 1kg starts to slide down from rest along a smooth slope with an inclination of 37 degrees. When it slides down for 4S, what is the instantaneous power of gravity? What is the average power of gravity in these 4 seconds? Take 10 G Hope to explain in detail

Acceleration a = gsin37 = 6
After 4 S, the velocity is 24 m / s,
Instantaneous power = force times velocity times cosine of angle between force and velocity
Instantaneous power = mgvcos53 = 144W
In 4S, the work done by gravity is equal to the change of kinetic energy, so the work done by gravity is 1 / 2 * m V ^ 2 = 288j
Average power P = w / T = 72W

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