Discover the Meaning of Δy in Projectile Motion Formula: A Comprehensive Guide

AI Thread Summary
The discussion clarifies that the formula Δy=[(sin2θ)(Vi)]^2/2a represents the maximum height a projectile can reach when launched at an angle θ with an initial velocity Vi, under the influence of gravity (a=9.8 m/s²). Participants note that the formula requires adjustments, specifically replacing sin2θ with sinθ for accuracy. The conversation emphasizes the relationship between the vertical component of velocity and the angle of projection. It also highlights the importance of rearranging equations to derive the maximum height formula effectively. Overall, the thread provides insights into understanding projectile motion and its mathematical representation.
staka
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I would like to simply know what Δy=[(sin2θ)(Vi)]^2/2a represents..
The formula only requires the angle and the initial velocity (along with the usual a=9.8m/s^2), so what height does the equation represent?
 
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The distance a projectile travels (over flat ground) is [sin(2θ)*(v^2)]/a, very similar to what you have there. Is there a chace you misread it?
 
well that's the distance..
I think I got it now though, it's possibly the maximum height over a flat ground.
 
Oh yeah you're correct, i just googled it a bit and it came up. It is the maximum height you reach
 
staka said:
I would like to simply know what Δy=[(sin2θ)(Vi)]^2/2a represents..
The formula only requires the angle and the initial velocity (along with the usual a=9.8m/s^2), so what height does the equation represent?
That's almost the formula for the maximum height of a trajectory. To correct it, replace sin2θ with sinθ.
 
So one of the famous equations for the motion of a projectile is as follows:

v2=u2+2as

v = final velocity
u = initial velocity
a = g = -9.8m/s2
s = distance travelled

Now, for a projectile being fired at an angle, the vertical component of velocity is usin%, where % is the angle between the ground and the direction of projection.

Rearrange your equation, with v=0 to get the maximum height attained by a projectile (note that in your equation, your v is my u).

You get:

s = u2/-2a = (usin%)2/-2a

As a = -9.8, you can ignore the minus sign and you basically have your equation (except for the sin2% bit).

Yes I don't know how to make greek alphabet symbols, so a % for an angle will do :D

Hope that helps.
 
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