If a car accelerates from rest at a constant 4 m/s , how long will it take for the car to reach a
velocity of 28 m/s?​

Time, t = 7 seconds.

Explanation:

Given the following data;

Initial velocity = 0m/s (since it is starting from rest).

Acceleration, a = 4 m/s²

Final velocity, v = 28 m/s

To find the time, we would use the first equation of motion given by the formula;

V = u + at

Substituting into the formula, we have;

28 = 0 + 4*t

28 = 4t

Time, t = 28/4

Time, t = 7 seconds.

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