Question

A crane lifts an I-beam to a height of 30m,giving it potential energy of 108,486 J. Calculate the mass of beam *

1. 1 point

2. 369 Joules

3. 359 Joules

4. 100 Joules

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Answer 1

Explanation:

Where U is potential energy, m is mass in kilograms, g is the acceleration due to gravity g=(9.81m/s2), and h is height is meters. Your equation h=E/mg is simply this formula rearranged to solve for height. All you need to do is plug in your values and solve for height.

Answer 2

Answer:

100 W`

`200 W`

`250 W`

`500 W`

Answer :

D

Solution :

Here `m = 100 kg, h = 10 m, t = 20s, g = 10 ms^(-2)`

`g = 10 ms^(-2)`

The power of the crane is

`P = (mgh)/(t) = ((100kg) (10 ms^(-2)) (10m))/((20 s)) = 5500W`

Explanation: