problem 1: A sled reaches the bottom of a hill where it slows from 18.0m/s to a stop in 25 m. Find out the force of friction if the sled has a mass of 75 kg?

problem 2: Two dogs are fighting over a bone. The first dog pulls with 200 N at 25º N of W and the second dog pulls with 185 N at 40º N of E. If the bone has a mass of 15 kg, determine its acceleration?

problem 3: A child is pulling their “little Red Wagon” all along a level sidewalk; they exert a force of 120 N via the handle that is angled at 12º above the horizontal. If friction resists with a force 45N, find out the acceleration of the 15 kg wagon?

problem 4:

a) A 2500 kg truck is rolling down an 18º hill. The force of friction is 6000 N; determine the acceleration of the truck?
b) If it begins from rest how fast will it be going after 50m?

problem 5: Slaves are building a pyramid in Egypt, to do this they pull 5000 kg blocks up a 10º incline at a constant velocity if the tension in the ropes they use is 10000 N, determine the force of friction?

problem 6: A lawn mower is pushed from rest to 2.5m/s in 4.0 m. Determine the work done if the mower has a mass of 30 kg?

problem 7:

a) In a soap box derby, racers have a rolling start (v = 2.5m/s) at the top of a 55.0 m high hill. What will their speed be at the bottom of the hill?

b) If the brakes of the racer apply a force 80 N to the 45 kg cart, how long will it take to slow down to 5.0m/s?