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This problem looks so simple but every answer I get is wrong...

EDIT : I realized several mistakes.. this is how I did it the last time:

I used the y-component of motion (free fall) to calculate time..

[tex]0 = 1 + v_0 sin (30) t- \frac {g}{2} t^2[/tex]

then I plug into this:

[tex]x_f = v_0 cos (30) t[/tex]

I have no idea what I'm doing wrong here... Ancy help would be much appreciated.

**A skateboarder starts up a 1.0-m-high, 30 degree ramp at a speed of 7.0 m/s. The skateboard wheels roll without friction.**

How far from the end of the ramp does the skateboarder touch down?How far from the end of the ramp does the skateboarder touch down?

EDIT : I realized several mistakes.. this is how I did it the last time:

I just tried it again... this time I calculated how long the ramp is which is 2 (since hight is 1 and sin 30 = 1/2). Now using this distance I calculated the final velocity the dude leaves the ramp with... then using that velocity I took the y-component of it and calcuated the time it takes to hit ground... used that time to calculate final position... and it was wrong.

I used the y-component of motion (free fall) to calculate time..

[tex]0 = 1 + v_0 sin (30) t- \frac {g}{2} t^2[/tex]

then I plug into this:

[tex]x_f = v_0 cos (30) t[/tex]

I have no idea what I'm doing wrong here... Ancy help would be much appreciated.

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