- #1

yellowcakepie

## Homework Statement

A fire hose for use in urban areas must be able to shoot a stream of water to a maximum height of 34 m. The water leaves the hose at ground level in a circular stream 4.0 cm in diameter.

What minimum power is required to create such a stream of water? Every cubic meter of water has a mass of 1.00×10^3 kg.

## Homework Equations

PE = mgh

r = 1/2d

A = πr^2

V = πr^2h = Ah

P = W/t = F*d/t = F*v

## The Attempt at a Solution

I converted the 4.0 cm diameter to radius in terms of meters, which is r = 0.02 m.

I solved for A, and multiplied A by maximum height (h) to get volume (V) which is 0.0427 m^3 column of water that is 34 m tall.

I used the density of water, which is 1000 kg/m^3 to get the mass of the column, which is 42.7 kg.

I don't really know where to go from here. I used PE = (42.7 kg)(9.8 m/s^2)(34 m), but I know that it is wrong. I'm not sure how to integrate the height of the column of water (if that's needed).