Question

You pull a wagon carrying your younger brother 1000 meters (1 km) to the store using 20 newtons of force the whole way. it takes you 15 minutes to get there. how much power did you generate, in joules per minute? in watts? 1333.33 joules/min you and a friend move a grand piano across the living room, exerting 25 newtons of force and performing 175 joules of work. it takes you 14 seconds. how far did you move the piano? how much power did you generate, in watts (joules/sec)?

Answer 1

Power generated while pulling the wagon is 22.22 watts or 1333.33 joules/min. The piano was moved 7 meters and the power generated was 12.5 watts.

Step-by-step explanation:

To calculate the power generated while pulling the wagon to the store, we need to understand that power is the rate at which work is done. Given you exerted a force of 20 newtons over a distance of 1000 meters, the work done is force × distance, which is 20,000 joules. Since it took you 15 minutes, we convert this to seconds (15 × 60 = 900 seconds) to find power in watts (P = work/time). Thus, the power in watts is 20,000 J / 900 s = 22.22 watts. To express this in joules per minute, we divide 20,000 J by 15 min to get approximately 1333.33 joules/min.

For the grand piano scenario, given the work (175 J) and the force applied (25 N), you can calculate distance using work = force × distance, rearranging to distance = work/force. This gives us a distance of 175 J / 25 N = 7 meters. To find the power in watts, divide the work (175 J) by the time in seconds (14 s), giving a power output of 12.5 W (175 J / 14 s).