Determining Range of Projectile Launched at 10 m/s

[Bingo1915]

1. A projectile is launched at 10 m/s
from a sloping surface. The angle $$\alpha=80 deg$$. Determine the range R.

2. Attached is the drawing.


3. Treat as 2 equations.

x-direction

Initial time t=0 Initial V$$_{x}$$=V$$_{0}$$Cos$$\theta$$

a$$_{x}$$dv$$_{}x$$/dt = 0

V$$_{x}$$=Initial VCos$$\theta$$ = dx/dt

Integrate and get
x=Initial V(Cos$$\theta$$)(t)
x=10(Cos80)(t)


Y-direction

a$$_{}y$$=-9.81 m/ss

V$$_{}y$$=-10Sin80



Im not sure if I am using the correct angle for theta (80 or 50) and I am stuck on the y-direction.
Can you help?

 

[physixguru]

never integrate projectile equations is all that what i will tell ya...

think differently...

 

[andrevdh]

What you can try is develop the kinematic equations normal to and along the slope. The accelerations are the components of g in the respective directions. You then set the normal position coordinate to zero as a condition to find the range .