A car accelerates uniformly in a straight line

Physics

1 answer:

julia-pushkina [17]3 years ago

8 0

The car travels a distance d from rest with acceleration a after time t of

d = 1/2 a t²

It covers 69 m with 2.8 m/s² acceleration, so that

69 m = 1/2 (2.8 m/s²) t²

t² = 2 (69 m) / (2.8 m/s²)

t ≈ 7.02 s

where we take the positive square root because we're talking about time *after* the car begins accelerating.

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