physics
posted by Sami on .
An arrow is shot from a bow at 20.0 m/s at an angle of 65 degrees above the horizontal. The arrow leaves the bow at a height of 1.80 m. At what height will it strike a wall that is 10.0 m away? (Remember to connect the two motions of the arrow using time.)

y = h + tanθ x  g/(2(vcosθ)^2) x^2
so, plug in x=10:
y = 1.8 + 2.144x  .580x^2
= 1.8+21.445.80
= 17.44
you can also use time, but it takes a bit more work:
Vx = 20 cosθ
use that to find t = 10/Vx
Vy = 20 sinθ
y = 1.8 + Vy t  4.9t^2
If you churn it out, it should come out the same. 
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