Calculating Time for Falling Crate in Projectile Motion

AI Thread Summary
To calculate the time it takes for a crate to hit the ground after falling from a cargo plane at 10.1 km altitude, the initial vertical velocity (Vyi) is zero since it falls straight down. The equations for vertical motion are used, with Yf set to 0m, Yi at 10100m, and gravitational acceleration (g) at -9.81 m/s². The relevant equation is Yf = Yi + Vyi*t - 4.905(t)^2, which simplifies to finding the time (t) when the crate reaches the ground. By solving this equation, the time of fall can be determined without considering air resistance. The solution requires substituting the known values into the equation.
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This is my first post here so please bear with me if I'm doing something wrong

Homework Statement



A cargo plane is flying horizontally at an altitude of 10.1 km with a speed of 910 km/h when a large crate falls out of the rear loading ramp. (Ignore any effects due to air resistance.) How long does it take the crate to hit the ground?

I converted everything to meters.

Yf = 0m
Yi = 10100m
Yxi = 252.78 m/s
g = -9.81 m/s

Homework Equations



Xf = Xi + Vxi*t
Yf = Yi + Vyi*t - 4.905(t)^2

The Attempt at a Solution



My problem is figuring out Vyi in this case so that I can plug it into my second equation to solve for time. Can anyone give me a push in the right direction?
 
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In the given problem vyi = 0.
 
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