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# Algebraic Projectile Motion Question watch

1. So i decided that projectiles weren't hard enough so i added algebra to them.

An object unaffected by air resistance, such as a particle in a vacuum, is projected from a ledge at an angle of x degrees with a velocity of 10ms^-1.

The object travels 3x^2 metres horizontally and 8x^2 vertically down from it's original position. What is the value of x?

I don't know if this is possible or if the value of x is complex or not but if anyone wants to try it then feel free. I will post an answer when and if i get one. I'm currently trying it now.
2. SO far all the answer looks like it is a real number which is reassuring.
3. use this formula:

http://www.brainkart.com/media/extra/EHMHtyY.jpg ( last line )

with x = 3x2

y = -8x2

u = 10

g = -9.8

Θ = x
4. (Original post by the bear)
use this formula:

http://www.brainkart.com/media/extra/EHMHtyY.jpg ( last line )

with x = 3x2

y = -8x2

u = 10

g = -9.8

Θ = x
Cool, thank you for the help.
I'm going to try doing it the long way as well just out of interest to see if i get the same answer or if i messed up one.
5. Did anyone try this? Or is it just too hard?
6. I found an answer. It is correct but not the interesting one that i was looking for. Just need to look for more.

Spoiler:
Show

It is 0

totally not predictable.
7. (Original post by Amullai)
Did anyone try this? Or is it just too hard?
The problem with your question is that it leads you to a transcendental equation whose solution can only be approximated. Your solution means it was launched from a height of 0, travelled 0 distance, when launched at an angle 0... it doesn't make sense.
8. (Original post by RDKGames)
The problem with your question is that it leads you to a transcendental equation whose solution can only be approximated. Your solution means it was launched from a height of 0, travelled 0 distance, when launched at an angle 0... it doesn't make sense.
Thank you for the help. I did find another answer on my calculator but it was only an approximation(at least i think it was).
9. (Original post by Amullai)
Thank you for the help. I did find another answer on my calculator but it was only an approximation(at least i think it was).
The approximate values I found were 1.381, 2.347, 3.809 in case you want to check.
10. (Original post by RDKGames)
The approximate values I found were 1.381, 2.347, 3.809 in case you want to check.
Ok thanks. I think i will.

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