Physics projectile motion question (with picture) - HELP!!!!!!!!!!!?

Question

The drawing shows a skateboarder moving at 5.4 m/s along a horizontal section of track that is slanted upward by 48 degrees above the horizontal at its end. Find his maximum height H above the end of the track.

http://img152.imageshack.us/img152/9967/ddasdqi5.jpg

Answer 1

Heres how i done it . . .

http://i28.photobucket.com/albums/c221/Scottie_Lass/physicsprojectileinmotion.jpg



I hope this helps =]

Answer 2

I will assume there is no friction (or air resistance)

First, I will determine his speed at the lip of the ramp using conservation of energy

.5*5.4^2*m=m*g*0.40+.5*m*v^2

where m is the mass of the skater and board, and g is gravity

v=sqrt(5.4^2-2*9.8*.40)

=4.62 m/s


When the skater becomes airborne, the vertical component kinetic energy will be converted to potential energy at apogee

.5*m*(4.62*sin(48)^2)=m*g*h

h=.5*(4.62*sin(48))^2/9.8

h=0.49 m

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