Projectile motion firehose question

AI Thread Summary
The discussion revolves around calculating the horizontal distance from a target at which a pilot should release a canister while flying at an altitude of 86.0 m and a speed of 69.0 m/s. The participant initially calculates the total time of fall to be approximately 4.189 seconds using the vertical motion equation. They then attempt to find the horizontal distance but mistakenly include vertical acceleration in their calculation. A participant points out this error, emphasizing that horizontal motion has no acceleration in this scenario. The conversation highlights the importance of distinguishing between vertical and horizontal motion in projectile motion problems.
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Homework Statement



In fighting forest fires, airplanes work in support of ground crews by dropping water on the fires. A pilot is practicing by dropping a canister of red dye, hoping to hit a target on the ground below.

if the plane is flying in a horizontal path at an altitude of 86.0 m above the ground and with a speed of 69.0 m/s, at what horizontal distance from the target should the pilot release the canister? Ignore air resistance.

Homework Equations



Any constant acceleration equation.

The Attempt at a Solution



ax=0
ay=-9.80

Xo= 0
Yo=86.0

Voy=0
Vox= 69.0

Vx=69.0
Vy=

y=0
x=

I first found Ttotal by using the equation 0-86.0=0+.5(-9.80)(t^2).

t = 4.189 seconds.

then I found Vy.

Vy= 0+(-9.8)(4.189)

Vy= -41.052

Then I realized finding Vy was a complete waste of time. ¯\_(ツ)_/¯

Then I tried to find x.

x-0 = (69.0)(4.189)+.5(-9.8)(4.189)^2

x = 203.05 m/s?

Does this look right?
 
Last edited:
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You are right down to where you found T total. In your last equation where you are calculating the value for x, you use an acceleration of -9.8. What is the acceleration along the x axis?(hint, you answered this when you state your value for ax.)
 
bacon said:
You are right down to where you found T total. In your last equation where you are calculating the value for x, you use an acceleration of -9.8. What is the acceleration along the x axis?(hint, you answered this when you state your value for ax.)

Oh, thanks for the catch, I really appreciate it!
 
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