Question

Each hour, a traditional double-seat chairlift can move 1200 people, having an average mass of 60.0 kg, up a ski hill. A high-speed quad chair can move 2400 people in 30.0 minutes up the hill. The upper terminal is 100 m higher than the lower terminal.

a.How much power would the traditional double-seat chairlift need to overcome the force of gravity?

Answer 1

This problem is tricky, because it can be read at different levels of complexity.

If you break down the power exerted by the lift, then you have:
- power needed to counteract weight
- power needed to accelerate the skiers from zero to velocity of lift
- power needed to compensate the friction between skier and chair (inelastic collision).

If the expected answer is just the first one, then it is fairly simple.
If the expected answer is the overall power (1+2+3), then it is not not straightforward, but it is very interesting.

Let us know what you can do with this.

Answer 2

i think i am just looking for - power needed to counteract weight @Vincent-Lyon.Fr

Answer 3

So you just need to estimate the work done against gravity and divide it by the time taken.