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## Homework Statement

Brandon and Tom are climbing a mountain. He starts from an elevation of H1=511m above sea level. In 6.18 hours he climbs to an elevation of H2=2746m above sea level. The length of his path is L1=16000m.

Brandon has a mass M1= 91.1kg and Tom has a mass M2=11.2kg

Vertical velocity up the mountain=0.0985m/s

Horizontal velocity down the mountain=0.141 m/s

A)Calculate the change in gravitational potential energy for Brandon and for Tom as they make their climb in the Rockies.

Delta GPE for Brandon=

Delta GPE for Tom=

B)Calculate the average kinetic energy for Brandon and for Tom as they climb up the mountain and as they descend.

KE for Brandon going up=

KE Tom going up

KE for Brandon coming down =

KE for Tom coming down=

## Homework Equations

A)GPE=mgh

B)KE=1/2mv^2

## The Attempt at a Solution

It seems to simple for question A is too simple to be true so I'm concerned about wether it is correct.

M computations:

GPE=mgh

=(91.1kg)(9.8m/s^2)h and (11.2kg)(9.8m/s^2)h

Question:What height should i use for h? Is this the right equation? What is meant by Change in gravitational energy,do I have to subtract them?

For B)

KE=1/2mv^2

KE for Brandon going up

KE=1/2(91.1kg)(0.0985 m/s^2)^2

=.441

KE Brandon going down

KE=1/2(91.1kg)(0.141 m/s^2)^2

KE=.905

Whats the units for KE?

Is this correct and if so should I do the same for Tom?