a skier in the snow starts to descend from a height of 30m from rest, at a certain speed he gets to 20 m/s How high is he? Urgent please help!

Question

cj7529 · Answer

If you equate the loss in potential energy to the gain in potential energy you get
mgh=0.5mv^2
m=mass
g=acceleration due to gravity =9.82 ~10
h=height
v = velocity

divide both sides by mg
h=[v^2]/[2g]
and sub in your values

shamim · Answer

$$v ^{2}=u ^{2}+2g(30-x)$$

shamim · Answer

here v=final velocity=20m/s
       u=initial velocity=0m/s
       x=height of the skier frm the bottom of the snow when his speed is 20m/s

shamim · Answer

if u hv any confusion abt gravitational acceleration g then i will tell abt g more. plz ask me

shamim · Answer

$$or, 20^{2}=0^{2}+2g(30-x)$$

shamim · Answer

$$or, 400=2 \times9.8(30-x)$$

shamim · Answer

$$or, x=30-\frac{ 400 }{ 2\times9.8 }$$

shamim · Answer

$$or, x=9.6 m$$

shamim · Answer

so the height of skier frm the bottom of the snow is  9.6m

shamim · Answer

when the velocity of skier is 20 m/s