A 1100-kg car pulls a boat on a trailer. (Enter the magnitude.) (a) What total force (in N) resists the motion of the car, boat, and trailer, if the car exerts a 1860-N force on the road and produces an acceleration of 0.600 m/s2

Spend time observing or thinking about events that involve matter and energy. which events can you explain? which events can’t you explain?

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground.what is his gravitational potential energy above the ground?

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".