Thursday

March 26, 2015

March 26, 2015

Posted by **Anonymous** on Sunday, June 29, 2014 at 1:06am.

- Physics -
**Damon**, Sunday, June 29, 2014 at 6:23amGuess mass of person, say 80 kg

guess how many on elevator, say 50 (guess high, we want a strong enough motor)

so total mass of people on elevator at one time = 80*50 = 4,000 kg

energy change = m g h

= 4,000 * 9.8 * 8 = 316,600 Joules

divide by 20 seconds

----> 15,688 Watts

If the efficiency is 40% then you need about a 40 kw motor

**Answer this Question**

**Related Questions**

physics - An escalator is 15.0 m long. If a person stands on the escalator, it ...

physics - In a mall, a shopper rides up an escalator between floors. at the top ...

geometry - an escalator lifts people to the second floor, 25 ft above the first ...

Physics - A person climbs from a Paris metro station to the street level by ...

Physics - A person climbs from a Paris metro station to the street level by ...

Physical Science - An escalator 14 m long is carrying a 70-kg person from one ...

Algebra 2 - If Graham runs up 6 steps of the escalator, then it takes him 46.5 ...

math - one elevator leaves first floor of a building at 9:00 a.m. It takes 5 ...

Ap Physics - An escalator in a shopping centre carries people up through a ...

Physics/Math - A person walks up a stalled 20 m long escalator in 79 s. When ...