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

In summary, Δy=[(sin2θ)(Vi)]^2/2a represents the maximum height reached by a projectile fired at an angle, with u as the initial velocity and a as the acceleration due to gravity. This is derived from the equation v2=u2+2as, with the vertical component of velocity being usinθ. The formula can be corrected by replacing sin2θ with sinθ.
  • #1
staka
23
0
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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  • #2
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?
 
  • #3
well that's the distance..
I think I got it now though, it's possibly the maximum height over a flat ground.
 
  • #4
Oh yeah you're correct, i just googled it a bit and it came up. It is the maximum height you reach
 
  • #5
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.
 
  • #6
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.
 

1. What is the equation for projectile motion?

The equation for projectile motion is: y = y0 + v0t + 1/2at2, where y is the vertical position, y0 is the initial vertical position, v0 is the initial velocity, t is the time, and a is the acceleration.

2. What is the difference between horizontal and vertical projectile motion?

Horizontal projectile motion involves motion in the x-direction, where the acceleration is zero and the velocity remains constant. Vertical projectile motion involves motion in the y-direction, where the acceleration is due to gravity and the velocity changes over time.

3. How do you find the range of a projectile?

The range of a projectile can be found using the formula: R = v0cosθ * (v0sinθ + √(v0sinθ)2 + 2gy0) / g, where v0 is the initial velocity, θ is the launch angle, g is the acceleration due to gravity, and y0 is the initial vertical position.

4. Can the projectile motion formula be used for non-uniform acceleration?

Yes, the projectile motion formula can be used for non-uniform acceleration by breaking the motion into small intervals and using the formula for each interval. This can provide a more accurate result for complex scenarios.

5. How does air resistance affect projectile motion?

Air resistance can affect projectile motion by slowing down the projectile's velocity and reducing its range. This is because air resistance creates a force in the opposite direction of motion, which decreases the projectile's acceleration and alters its trajectory.

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