Free fall and distance traveled question.

AI Thread Summary
The discussion revolves around a physics problem involving four villains on motorcycles driving off a parking garage. The key point is that all riders take off horizontally with zero vertical velocity, meaning they all experience the same time of flight regardless of their initial speeds. Thus, the correct ranking of their times of flight is A=B=C=D. The confusion stemmed from misapplying acceleration and the lack of an angle or height in the problem. Ultimately, the solution highlighted the simplicity of the scenario, emphasizing the importance of understanding the principles of projectile motion.
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Homework Statement


(Yes this is a question about Batman.)

To escape from Batman, 4 villains on motorcycles drive
horizontally off the edge of a parking garage, landing in a pile
of sand. The riders all have different initial speeds: v0A =
14m/s, v0B = 24m/s, v0C = 18m/s, and v0D = 19m/s. Rank
these four riders in order of time of flight, from shortest time to
longest, with no spaces, using < or = symbols between them.
For ties, list answers alphabetically. For example: D<A=C<B


Homework Equations


Xf = Xi + Vix*dT + (1/2)a*dT^2

Vfx = Vix + a*dT

Vfx^2 = Vix^2 + 2a*dT

Xf = Xi + (1/2)(Vix + Vfx)*dT

The Attempt at a Solution


My first thought was to take a stab at finding Xf, and then finding delta T, but after going through with this my answer ended up being wrong. This is the information I gathered from the problem... It seems that I made my list wrong as I listed the horizontal acceleration as g when it shouldn't be, so I'm left with this.
Xi = 0
Xf = ?
Vix = Vo
Vfx = ?
ax = 0
dT= ?

Yi = ?
Yf = 0
Viy = ?
Vix = ?
ay = -g

This question really has me stumped. There's no angle theta and initial height of the building to help me out, so I'm confused.
 
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To escape from Batman, 4 villains on motorcycles drive
horizontally off the edge of a parking garage, landing in a pile
of sand.
------------
Since all took off horizontally, thus zero vertical velocity, and landed on the same level, time of all flights are all equal.
A=B=C=D.
 
azizlwl said:
To escape from Batman, 4 villains on motorcycles drive
horizontally off the edge of a parking garage, landing in a pile
of sand.
------------
Since all took off horizontally, thus zero vertical velocity, and landed on the same level, time of all flights are all equal.
A=B=C=D.

Thank you so much! I can't believe it was that simple... I suppose I should stop over-thinking this stuff.
 
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