physics help!?

Question

Can someone please explain step by step how to solve this question... i have been trying to solve for an hour!

A skier starting from rest accelerates uniformly downhill at 1.8 m/s^2 (fwd) . How long will it take the skier to reach a point 95 m (fwd) from starting position?

any help would be greatly appreciated :-)

Answer 1

Just look through the linear acceleration equations and find one that meets your requirements.



The equation to use here is s = ut + 1/2at^2 where



s = displacement (in this case 95m)

u = initial velocity (in this case 0)

a = linear acceleration (in this cas 1.8 m/s^2)

t = time (which is the value you will be solving for)



Sub your known values into this equation and manipulate to solve for t. Try it yourself if you want, or just check my solution.



95 = 0t + 1/2(1.8)t^2

95 = 0.9t^2

95/0.9 = t^2

950/9 = t^2



solve using calculator for t = +/-(10.274)

however time is a scalar so the negative answer is impossible

t = 10.274

Answer 2

s=ut+½at²

s= 95m, a=1.8m/s², u=0

s=0*t+½*1.8*t²

95 = .9t²

t²=95/.9=105.55

t=√105.55=10.27 sec

In 10.27 seconds the skier will reach a point 95 m from the starting position.

Answer 3

Speed Divided by Distance = Time

So 95/1.8=52.8 seconds..

Well i think anyway!

Answer 4

dude u need to use the formula s=ut+0.5at^2



s=95,a=1.8.



==> t=(square root)2s/a



=(sqr root)2*95/1.8



=(sqr root)105.55



answer =10.3 seconds