A 67 kg hiker climbs to the top of a 3700 m-high mountain. The climb is made in 5.5 h starting at an elevation of 2800 m. Calculate assuming the body is 16% efficient, what rate of energy input was required.

Ummm no one else is using this computer. I am the only one using it. It may be people from my class, because its a large lecture and the teacher mentioned this site today. Now I want to tell the professor to never recommend this site again.

Kristie, Kathleen, Lauren, or whoever --

This looks like homework dumping. A physics tutor is more likely to respond if you include what YOU KNOW about each problem, what YOU THINK about finding each answer.

I don't know about Kathleen or Lauren or whatever I just had a question about this problem. I really didn't know what to do and thought maybe this site could help, but if people like this answer maybe this isn't where I should come for help.

To calculate the rate of energy input required, we need to find the total energy expended during the climb. We can do this by calculating the change in potential energy.

The change in potential energy (ΔPE) is given by the formula:

ΔPE = m * g * Δh

where:
m = mass of the hiker (67 kg)
g = acceleration due to gravity (9.8 m/s²)
Δh = change in height (3700 m - 2800 m = 900 m)

ΔPE = 67 kg * 9.8 m/s² * 900 m
ΔPE = 587,220 J (joules)

However, the hiker is only 16% efficient, meaning that only 16% of the energy input is converted to useful work. Therefore, we need to calculate the total energy input (TEI) required using the formula:

TEI = ΔPE / efficiency

TEI = 587,220 J / 0.16
TEI ≈ 3,670,125 J (joules)

So, the rate of energy input required is the total energy input divided by the time taken:

Rate of energy input = TEI / time

Rate of energy input = 3,670,125 J / 5.5 h
Rate of energy input ≈ 667,296 J/h (joules per hour)

Therefore, approximately 667,296 joules per hour of energy input was required for the hiker to climb the mountain.

If you don't know about these others, why are you all using the same computer and asking similar questions about the same time?