More Projectile (1 Viewer)

[HoldingOn]

http://prntscr.com/k9ehx7

Part iii. And any tips for these inequality style projectile questions? I'm not great at them. Thanks

 

[fan96]

Note that the ball will hit the net if and only if the net is placed within the ball's horizontal range.

 

[HoldingOn]

Note that the ball will hit the net if and only if the net is placed within the ball's horizontal range.

Yes but for some values won’t the ball fly over the net ? Because the net doesn’t exceed the maximum height

 

[fan96]

Yes but for some values won’t the ball fly over the net ? Because the net doesn’t exceed the maximum height

Oh sorry I forgot about that.

In this case you would start by finding exactly where the ball is at a height of 30m (there will be two times - a diagram may help).

Then, knowing that the trajectory of the ball is a concave down parabola, you can deduce when the ball is at a height of less than 30m, which is where it can hit the net.