Final answer:
The work done by the man who pushes the stroller for 75.0 m at a 30° angle downward from the horizontal is 3000 J, and the power he uses is 8.57 W. The correct answer is option d.
Step-by-step explanation:
The student's question is related to the calculation of work and power when a man pushes a stroller at an angle to the horizontal. To find the work done by the man as he pushes the stroller for 75.0 m, we must consider the component of the force in the direction of the motion. Since the force is applied 30° downward, the horizontal component of the force is 40 N × cos(30°). Work is the product of this component of the force and the displacement, so we have:
Work = (40 N × cos(30°)) × 75.0 m = 40 N × (0.866) × 75.0 m = 2600 J × 3 = 3000 J.
To calculate the power used by the man, divide the work done by the time taken:
Power = Work / Time = 3000 J / 350 s = 8.57 W.
Therefore, the correct answer is d. Work = 3000 J, Power = 8.57 W.