Why Can't I Use V = Vo + at to Calculate Time for a Car Falling Off a Cliff?

AI Thread Summary
The discussion centers on the confusion surrounding the use of the equation V = Vo + at to calculate the time it takes for a car to reach 100 km/h after rolling off a cliff. The initial velocity (Vo) is zero, and the acceleration due to gravity (a) is 9.8 m/s². However, this equation is not applicable in this scenario because the car is in free fall, and the vertical motion does not directly correlate with the horizontal speed. The correct approach involves understanding the relationship between vertical distance and time, as well as the conversion of speed units. Ultimately, the user realizes their mistake and finds the solution.
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ok I've just cracked the ****s, for this question:

A car rolls gentley(Vo=0 m/s) off a vertical cliff. How long does it take for it to reach 100km/hr.

why can't i use V = Vo + at
where:

V= 100
Vo = 0
a = 9.8(gravity)
t = ?

the only equations I've been given to do this are:

V = Vo + at
V^2 = Vo^2 + 2ax
x=Vot + 1/2at^2

ARGGGGGHHHHHHHHHHHHHHHHHH!
 
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Thats a good question, why can't you use it?
What did you get for an answer using it?
 
dont worry i got it, stupid me
 
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