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Free fall and distance traveled question.

  • Thread starter Freemark
  • Start date
  • #1
14
0

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.
 

Answers and Replies

  • #2
1,065
10
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.
 
  • #3
14
0
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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