Calculating Energy Requirements for Human Activity on Inclined Surfaces

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To calculate the height of a hill that would require 9,000,000 J of energy for a 52 kg person walking up at a 12-degree incline, the formula Eg = mgh should be used, where h is the vertical height. The energy consumed relates to the vertical displacement, not the total distance traveled along the incline. Gravity does work against the person's movement, and this work can be calculated using the same formula, considering the height gained. Energy is a scalar quantity, meaning it does not have direction, unlike vectors. Understanding these principles is crucial for solving the problem accurately.
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here is a question that I am unable to solve:

The average human, of mass 52 kg needs to have approximately 9,000,000 J of energy per day. Suppose, you had to walk up a hill with an incline of 12 degrees. Determine the following:
a) how high would the hill have to be (i.e. - change in height) in order to consume all of this energy.
b) how much work did gravity do in all of this walking?

for A, i know you have to use the formula Eg=mgh but i am not sure where to sub in the energy as 9,000,000J or sin 12*9,000,000 (since its at an angle)

B) i don't knoe what role gravity plays in this?
 
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Originally posted by Ambitwistor
In the formula mgh, h refers to just the vertical displacement, not the total distance.

sorry, but you haven't answered my question? directly
 
SO, energy is not a vector quantity?
 
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