# The angle @ which the particle hits the wall

1. Nov 28, 2007

### ranaroy

dear all,

i am working on a problem, but not having found the solution yet.
i have a wall section (in a 2D x-y plane) on which spherical balls hit and get reflected.
i know the x-velocity and y-velocity of the particle when it hits the wall.
i need to calculate the impact (incident) angle of the ball on the wall.

it is easy to calculate when the plane is either along x-axis or y-axis. but, my plane is curvilnear (i know the radius of curvature). can i calculate the incident angle for this curvilinear plane ?

pls help. thank you.

2. Nov 28, 2007

### ASAPLZ

I don't know this very well, but here's a shot. Take the angle it hits the and copy that same angle it hits on the wall and add the curvilinear to the other side.

3. Nov 28, 2007

### ranaroy

dear asaplz,

can u explain it once more in detail. i didnt understand well.
you mean to say, first i will do theta = atan(V_y/V_x) and calculate the angle.
then, what shoud i do ?

to make it more clear for me, can u do one example case.
say V_y = 3 m/s , V_y = 4 m/s
So, theta = 37 degree.

pls help

4. Nov 28, 2007

### ranaroy

sorry, the above velocity components should read
V_y = 3 m/s , V_x = 4 m/s

sorry for the mistake.