Physics - conservative and non conservative (check

If a sled reaches the base of the hill with a speed of 15.6m/s, how much work was done by the snow on the sled between points x and y, where x is 3m above the ground with a velocity of 14.30m/s and y is toughing the ground. the sled and the rider are 70kg Ans: i tried the formula work done = Ek+Ep, where Ek =(0.5)(70)(15.60)^2 and Ep= (70)(9.81)(2) i get 7157j which is incorrect, where am i going wrong?


Your calculation of kinetic energy (Ek) is correct. The problem is with the calculation of potential energy (Ep). In this case, the change in potential energy is equal to the work done by the snow. Thus, the potential energy must be equal to the work done (7157J). To calculate the potential energy, you need to use the formula Ep = mgh, where m is the total mass of the sled and rider (70kg), g is the gravitational acceleration (9.81m/s2), and h is the height difference between points x and y (3m). Doing the math, we get Ep = (70)(9.81)(3) = 2126.7. This means that the work done by the snow is equal to the change in potential energy, which is 2126.7J.

Answered by Steven Benson MD

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