How do I find the work and power if I have a mass in Newtons?

AI Thread Summary
To find work when climbing stairs, it's essential to convert weight correctly into Newtons without unnecessary multiplications. The user initially converted their weight of 135 pounds to Newtons using a factor of 4.5, resulting in 607 Newtons. However, multiplying by 9.8 m/s² again was incorrect, as the force is already expressed in Newtons. Work is calculated as force multiplied by distance, so only the force in Newtons and the distance in meters should be used. Clarifying units and avoiding redundant calculations is crucial for accurate results.
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Im trying to find my work when climbing up stairs. If I convert my weight into Newtons, do I still need to multiply it by 9.8? Since i weigh 135, I multiplied that by 4.5 to get my weight in Newtons. I then multiplied that by 9.8, after that I multiplied that by 3.0 m ( the distance of the stairs). I got a really big number

that okay?
 
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Why did you multiply by 4.5? 135 what?
 
135 pounds

1pound=4.45 Newtons
 
So then why did you multiply by 9.8 again if you already have your weight in Newtons?
 
No, it's not ok. You only put units on the height of the stairs. Put units on EVERYTHING. You weight 135? 135 what? I'm guessing lbs. Don't make me guess. So then 135lb*4.5N/lb=607N is already a force unit (Newtons=kg*m/sec^2). I'm guessing when you said 9.8 you mean 9.8m/sec^2. Work is force times distance. Is 607N*9.8m/sec^2 even a force unit? Can you answer your own question? "If I convert my weight into Newtons, do I still need to multiply it by 9.8?". Yes or no?
 
no, you dont..

okay, thanks

let me change my data

thanks
 

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