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# Question- projectile motion? watch

1. Why use V=S/t if it's asking for horizontal velocity. Shouldn't you use x=Ut?
2. (Original post by Questioness)

Why use V=S/t if it's asking for horizontal velocity. Shouldn't you use x=Ut?
both are just different ways of stating the relationship between velocity, length and time... you can get from one to the other with a little algebra.
3. (Original post by Questioness)

Why use V=S/t if it's asking for horizontal velocity. Shouldn't you use x=Ut?
Theyre exactly the same thing
4. (Original post by Questioness)

Why use V=S/t if it's asking for horizontal velocity. Shouldn't you use x=Ut?
X = ut is the same thing as S = vt.
It's derived from the equation s = ut +1/2at^2.Because we are talking about the horizontal velocity we know that v = u. The ball has reached a constant velocity so it's acceleration is 0.
Substitute this in : S = vt + 1/2(0*t^2).
End result S = vt
5. (Original post by swellow5)
X = ut is the same thing as S = vt.
It's derived from the equation s = ut +1/2at^2.Because we are talking about the horizontal velocity we know that v = u. The ball has reached a constant velocity so it's acceleration is 0.
Substitute this in : S = vt + 1/2(0*t^2).
End result S = vt
Incredibly overcomplicated. V=s/t. V is constant horizontally so u=x/t, where x is horizontal displacement
6. (Original post by samb1234)
Incredibly overcomplicated. V=s/t. V is constant horizontally so u=x/t, where x is horizontal displacement
Yeah I know, this is my first post though so I thought I should explain it in detail. Next time will keep it short buddy
7. (Original post by swellow5)
Yeah I know, this is my first post though so I thought I should explain it in detail. Next time will keep it short buddy
Lol im not having a go at you, just thought it might be useful to the op to realose that there is literally no difference between the two formualas. There is no need to do any algebra because the formulas are literalky the same thing

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