I HATE wordproblems

algebrapro18

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If anyone can solve these two problems I will find something to give you.

1) A 160-lb man carries a 25-lb can of paint up a helical staircase that encircles a silo with a radius of 20ft. If the silo is 90ft high and the man makes exactly three complete revolutions, how much work is done by the man against gravity in climbing the stairs.

2) Suppose there is a hole in the can of paint in the above problem and 9lbs of paint is steadily leaking out of the can during the mans ascent. How much work is being done?

Hint: Use Line Integrals to calculate work.
 

butzie

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Okay, I can't take credit for this because I asked my Mechanical Engineer husband to solve it. Here is his solution:

First of all, he says that the helical staircase is irrelevant and does not figure into the equation. So,

1) The answer is 90(160 + 25) = 16,650 foot-pounds

2) You are losing 9 pounds of paint over time, so this is equivalent to lifting 9/2 = 4.5 for the full trip. 25-4.5 = 20.5. 90(160+20.5) = 16,245 foot pounds.

He didn't need linear integrals.

Hope it helps.
 

butzie

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Originally Posted by Skippymjp

Always use liquid fueled rockets when launching paint cans indoors. They smoke less that the solid fuel ones...
You are going to make one heck of a moderator.
 

butzie

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Originally Posted by CarolPetunia

Can't help with staircases, but if they give you something with trains, call me...
Are you talking about problems that were: "If one train leaves station A traveling at x speed and Train B..." I always hated those problems and wished the
trains would collide.
 
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algebrapro18

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Thanks Butzie but I have to do it using line integrals because this is for my calculus class not a physics class but I will send you a gift anyway, I just need to figure out how to do that. And now I can check my work with your husbands answers.
 
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