35 An object moving with uniform acceleration changes its speed from 25 m/s to 45 m/s in 5.0 s. Its acceleration is (a) 4.0 m/s (b) 4.0 m/s2 (c) 9.0 m/s2 (d) 14 m/s (e) 14 m/s2 36 The following graph represents a displacement-time graph for an object during a 5 s time interval. Displacement O 2 3 5 Time (s) Which one of the following graphs of velocity versus time would best represent the velocity of the object during the same time interval? (A) Velocity o Time (s) (B Velocity Un L Time(s) Velocity 2 3 5 Time (s) (D) Velocity 2 3 5 Time (s) 41 E Velocity 2 Time (s)37. Two carts, A and B, having spring bumpers, undergo an elastic collision. Cart A has a mass of 75 kg and is initially moving to the right with a speed of 6.0 m/s Cart B is initially at rest and its mass is not known. Consider all motion to the right as being positive, and assume that during the collision interval the two carts exert a constant repulsion of 150 N on each other. Initial direction of motion of A Initially at how Bo rest Horizontal, frictionless table What is the total momentum of carts A and B relative to the table after the collision? (a) Zero (b) 225 kg.m/s (c) 300 kg.m/s (d) 450 kgim/s (e) It cannot be determined without additional information. 38. A mass m moving with speed v, has a constant force of friction F acting on it. In order to increase its speed to v2 over a distance d, the total work that must be done is 1 (a) 1 ( b ) 2 mus (c) ?m(vitvi) -m( v2 - vi ) + Fd (d) 2 m(v3 - vi)+ Fd (e)