Hey just gettin a bit stuck on this question.....i'll attempt to answer it, but it really doesn't look right to me.(adsbygoogle = window.adsbygoogle || []).push({});

A cable car is used to carry people up a mountain. The mass of the car is 2000kg and it carries 80 people, of average mass 60kg. The vertical height travelled is 900m and the time taken is 5 minutes.

i) Calculate the gain in GPE of the 80 people in the car

GPE = mg/\ h

= (80 x 60) x 9.81 x 900

= 4.2 x 10^7 J

Is this right so far?

ii) Calculate the minimum power required by a motor to lift the cable car and its passengers to the top of the mountain.

Power = Work Done/Time Taken

Work Done = Force x Distance = (4800 + 2000) x 9.81 x 900

= 6.0 x 10^7

Power = (6.0 x 10^7) / 300 (as 5 mins = 300s)

P = 2.0 X 10^5 watts

These are the answers I got........i think i've used the right method, just need some reassurance!

Thanx in advance!

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# Homework Help: GPE Question

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