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Im confused, help...

Hello, how do i do this question?
A rugby player is aiming for a conversation. He kicks the ball at 15ms^-1 at an angle of 50° to the horizontal. At the time, he is 20m from the posts. How long will ball take to reach the posts? How high will the ball be when it reaches the posts?
Hi! You will need to break the ball's velocity down into its vertical and horizontal components.

The vertical component is equal to 15m/s times sin(50˚). The horizontal component is 15m/s times cos(50˚).

Given the horizontal component of the velocity and the distance of the kicker from the posts, you can work out how long it will take the ball to reach the posts, since the horizontal component won't change with gravity (and we're ignoring air resistance presumably).

Then you can plug the amount of time you've just derived, the initial vertical component of the ball's speed, and acceleration due to gravity (9.8 m/s/s towards the ground or whatever approximation your class is using) into the right SUVAT equation to determine how high the ball will be when it reaches the posts. Remember that if we're defining positive vertical distance as up, acceleration due to gravity should be considered negative.

Good luck!
Side note: "aiming for a conversation" - is that a rugby term? I don't really know the first thing about rugby...
Original post by anosmianAcrimony
Side note: "aiming for a conversation" - is that a rugby term? I don't really know the first thing about rugby...

No, i meant conversion. Sorry.
Original post by anosmianAcrimony
Side note: "aiming for a conversation" - is that a rugby term? I don't really know the first thing about rugby...

Also, thank you.

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