Stuck on some Physics, help please (Work and Energy)?

AI Thread Summary
To determine the speed of a skeleton racer at the bottom of a 104m track, apply the principle of conservation of energy, where potential energy converts to kinetic energy, allowing calculation of speed. For the ski lift problem, average power can be calculated using the formula power = work/time, where work is the product of the force (weight of the skiers) and the height raised. The weight of the skiers can be found by multiplying their mass by gravitational acceleration. Understanding these concepts will clarify how to approach both problems effectively. Assistance in grasping these physics principles is crucial for solving the stated problems.
Marcelgluch
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Stuck on some Physics, help please! (Work and Energy)?

K this first one I am not sure how to do it.. i did the second part, that's because i had all the variables but in this one i dont...

ok this is about skeleton racers... the track total height is 104m, in the absence of nonconservative forces, such as friction and air resistance, what would be the speed of a rider at the bottom of the track? ignore initial velocity since its relatively small.

and

In 2.0min a ski lift raises four skiers at constant speed to a height of 140m. the average mass of each skier is 65kg. what is the average power provided by the tension in the cable pulling...

i know what to but i just can't figure out the Work... i know that power = work/time.. so if i could get some help that would be greatly appreciated!
 
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can someone please help me understand these two problems??
 

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