Physics

Struggling with physics question.
If a ball weighing 2kg is kicked over some rugby posts 3 meters high 21 meters away at 60 degree angle what would be the minimum force required for the ball to go over the posts?
Air resistance and other factors are negligible

Reply 1

charlie.R.12

Original post by Bri4

its a bit of a weird question this. ive just finshed my alevel doing AQA and had never seen any questions like this and have done thousands of them. My best guess at a way of working it out is to start by treating it as a projectile motion question and find the initial velocity needed to get the ball over the post. Then you can use mass x velocity to find the momentum of the ball after being kicked however this is why i called it a weird question as the force is dependent on the time the ball and foot are in contact as the change in momentum is equalt to the impulse force acting on it. So in theory you could have any force acting on it even one newton if its applied long enough by the foot ( obviosly only in a theoretical world) so without knowing the contact time between foot and ball im not sure you can know the force.

Take this with a pinch of salt as its been about three months since ive even thought about any physics and its pretty likely someone with a better knowledge of phsyics knows how to find it out but for my knowledge this is all i could think of.