The discussion centers on calculating the displacement of a car decelerating at a rate of 20 km/h/s, starting from an initial velocity of 50 km/h and ending at a final velocity of 5.0 m/s. The incorrect calculation initially yielded a displacement of 54.4 m due to a failure to convert units properly. The correct displacement, after proper unit conversion, is determined to be 15 m using the equation vf² = v₀² + 2aΔx.
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Natko said:Homework Statement
A car is slowing down at a rate of 20 km/h/s. How far does it travel if its original velocity is 50 km/h and its final velocity is 5.0 m/s?
Homework Equations
vf2 = v02 + 2aΔx
The Attempt at a Solution
vf2 = v02 + 2aΔx
Δx = (vf2 - v02) / 2a
= (182-502) / 2(-20)
= -2176 / -40
= 54.4 m
That's wrong, though. The answer should be 15 m.