Calculating Work Load: 55kg Mass Walking up 20 Steps

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To calculate the work done by a person with a mass of 55 kg walking up 20 steps, each 20 cm high, the total height is 4 meters. The work formula W=FxD requires the force (weight) calculated using F=mg, where g is approximately 9.8 m/s². The resulting force is 539 N, and the displacement is 4 m, leading to a total work of 2,156 Joules, which rounds to 2.2 x 10^3 Joules. The discussion emphasizes the importance of using the correct value for gravitational acceleration and the significance of significant figures in the final answer. Understanding these calculations is essential for accurately determining workload in physics problems.
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A person with mass 55kg walks at a constant speed up a set of stairs with 20 steps, each 20 cm high.


I have to find the work load.
Formula: W=FxD where F is force and D is displacement.

The book says my answer should be 2.2x10^3. OR 2,200 Joules.

I really don't know how to do this. Please help me :)
 
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SailorMoon01 said:
A person with mass 55kg walks at a constant speed up a set of stairs with 20 steps, each 20 cm high.


I have to find the work load.
Formula: W=FxD where F is force and D is displacement.

The book says my answer should be 2.2x10^3. OR 2,200 Joules.

I really don't know how to do this. Please help me :)

20 steps each 20cm high totals 4m.
How much work is done raising a 55 kg mass through 4 m. That could be a good start.
I wonder whether you are supposed to take the value of g as 9.81, just 9.8 or perhaps even a round 10.
 
9.8 is probably fine, considering the answer and all the values given only have two sig figs.
 
tal444 said:
9.8 is probably fine, considering the answer and all the values given only have two sig figs.

If you want to get 2.2 x 103N that would be fine, but if you want to get 2200 it is not. My statement was a hint rather than a puzzle to me.
 
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