Asled is pushed along an ice covered lake. it has some initial velocity before coming to rest in 15m. it took 23 seconds before the sled and rider came to a rest. if the rider and sled have a combined mass of 52.5 kg, what is the magnitude and direction of the stopping force? what do we call the stopping force?

Astone is dropped from the upper observation deck of a tower, 250 m above the ground. (assume g = 9.8 m/s2.) (a) find the distance (in meters) of the stone above ground level at time t. h(t) = (b) how long does it take the stone to reach the ground? (round your answer to two decimal places.) s (c) with what velocity does it strike the ground? (round your answer to one decimal place.) m/s (d) if the stone is thrown downward with a speed of 2 m/s, how long does it take to reach the ground? (round your answer to two decimal places.) s