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1. Homework Statement
These are the exact words:
A player is ready to throw a ball with max. possible velocity of 15 m/s from a height of 1.5 m above the ground. He wants to hit the wall 16 m away from him at its highest point. If the ceiling height of the room is 8 m, find the angle of projection of the ball and the height of the point where the ball hits the wall.
2. Homework Equations
v=u+at
s=ut+0.5t^2
v^2=u^2+2as
3. The Attempt at a Solution
The attached file is the diagram.
To find α, I did this:
##15\cos(\alpha)=\frac{16}{t}##
##0=15\sin(\alpha)9.81t##
## \therefore 15\sin(\alpha)=\frac{9.81\times16}{15\cos(\alpha)} ##
## \therefore 15^2\sin(\alpha)\cos(\alpha)=9.8\times16 ##
## \therefore \sin(2\alpha)=\frac{2\times9.81\times16}{15^2} ##
## \therefore \sin(2\alpha)=1.3952 > 1 ## < WHAT
Did I do something wrong?
These are the exact words:
A player is ready to throw a ball with max. possible velocity of 15 m/s from a height of 1.5 m above the ground. He wants to hit the wall 16 m away from him at its highest point. If the ceiling height of the room is 8 m, find the angle of projection of the ball and the height of the point where the ball hits the wall.
2. Homework Equations
v=u+at
s=ut+0.5t^2
v^2=u^2+2as
3. The Attempt at a Solution
The attached file is the diagram.
To find α, I did this:
##15\cos(\alpha)=\frac{16}{t}##
##0=15\sin(\alpha)9.81t##
## \therefore 15\sin(\alpha)=\frac{9.81\times16}{15\cos(\alpha)} ##
## \therefore 15^2\sin(\alpha)\cos(\alpha)=9.8\times16 ##
## \therefore \sin(2\alpha)=\frac{2\times9.81\times16}{15^2} ##
## \therefore \sin(2\alpha)=1.3952 > 1 ## < WHAT
Did I do something wrong?
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