What Is the Rate of Change of Momentum When Water Hits a Building?

AI Thread Summary
The problem involves calculating the rate of change of momentum for water hitting a building from a fire hose delivering 2528 gallons per minute at a speed of 28 m/s. The user converted gallons to kilograms and found the flow rate to be 159.5 kg/s. They then multiplied this by the velocity to attempt to find the momentum change but arrived at an incorrect value. Other participants suggest rechecking the arithmetic to identify any calculation errors. The discussion emphasizes the importance of accuracy in the calculations to solve the problem correctly.
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Tried this problem, but not getting it.

Homework Statement


A fire hose sends 2528 gallons of water per minute against a building. The water strikes the building at 28 m/s and does not bounce back. What is the magnitude of the rate of change of momentum of the water?

Homework Equations


The Attempt at a Solution


I used the conversion factor of 1 gallon / 3.7856 L and 1 kg / 1 L to find how many kg of water per minute. Then divided by 60 to find how many kg of water per second. I got 159.5 kg of water per second. Then I multiplied by the velocity to get 4466, but I did not get it correct. Am I on the right track or missing something? PLEASE HELP!
 
Last edited:
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You seem to be doing it correctly. Check your arithmetic once more.
 

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