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Projectile motion-Golfer hitting ball at angle 60degrees

I am a little confused about projectile motion, specifically because the different materials that I am working with seem to give different information.

See attached:



2.png




So, if I break the parabola into two parts.

The first part has both horizontal and vertical forces independent of each other.

Am I right to say that the final velocity for the vertical force is 0? The vertical force is the point at which the ball reaches its maximum height before gravity accelerates it to Earth.

See my workings.


Screenshot_20240517_133556_Noteshelf.jpg
The solution suggested by my course approaches it differently.
Can I presume that they're approaching it from the journey as one? From the moment the ball is hit, and the moment it touches the ground? Hence, their final velocity is -20
(edited 2 months ago)
Reply 1
There are a few things that are probably worth noting

using s for horizontal speed is confusing as you use that for displacement. You could simply write s=ut when the acceleration is zero

gravity always acts on a body, not just past the peak vertical height

there is no need to calculate the vertical peak height

You should do v-u=at vertically (which you do) to get the time to peak then double it to get the range time (or use v=-u to get range time directly) and use the range time in the horizontal s=ut. Your "flow" is confusing

Youd have to upload what the model solution was to comment on it.
(edited 2 months ago)
Reply 2
Original post by mqb2766
There are a few things that are probably worth noting

using s for horizontal speed is confusing as you use that for displacement. You could simply write s=ut when the acceleration is zero

gravity always acts on a body, not just past the peak vertical height

there is no need to calculate the vertical peak height

You should do v-u=at vertically (which you do) to get the time to peak then double it to get the range time (or use v=-u to get range time directly) and use the range time in the horizontal s=ut. Your "flow" is confusing

Youd have to upload what the model solution was to comment on it.

I am approaching it the same way a video that I watched did. https://www.youtube.com/watch?v=9thdmEdCcKw

Perhaps it isn't good practice to copy someone else lol
Reply 3
Original post by KingRich
I am approaching it the same way a video that I watched did. https://www.youtube.com/watch?v=9thdmEdCcKw
Perhaps it isn't good practice to copy someone else lol

You got the answer, but your explanation is dodgy which is arguably more worrying. Really its a basic parabolic motion question using v=u+at vertically and s=ut horizontally, which is a few simple lines.
Reply 4
Original post by mqb2766
You got the answer, but your explanation is dodgy which is arguably more worrying. Really its a basic parabolic motion question using v=u+at vertically and s=ut horizontally, which is a few simple lines.

Yeah, if you were doing this course you'd find their explanation confusing, too. Lol. In the end, I'm just turning to YouTube for explanations and seeing how it aligns with the text I've been told.

I do see what you mean. I'm starting to get fed up with this course to be honest.

However, without it, I won't be able to go to uni, so unfortunately, I have to try and make sense of it the best I can.
Reply 5
Original post by KingRich
Yeah, if you were doing this course you'd find their explanation confusing, too. Lol. In the end, I'm just turning to YouTube for explanations and seeing how it aligns with the text I've been told.
I do see what you mean. I'm starting to get fed up with this course to be honest.
However, without it, I won't be able to go to uni, so unfortunately, I have to try and make sense of it the best I can.

Sure but this is a standard (reasonably easy) a level problem, so maybe use tlmaths or ... to cover the material and use the other notes once you feel you understannd the topic.

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