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If a car can accelerate at 3.2 m/s² from rest to 64 m/s, how long will it take?

a) 10 s
b) 20 s
c) 30 s
d) 40 s

1 Answer

1 vote

Final answer:

To determine the time it takes for a car to accelerate from rest to 64 m/s at a rate of 3.2 m/s², use the kinematic equation, resulting in a calculation of 20 seconds.

Step-by-step explanation:

If a car can accelerate from rest at 3.2 m/s² to a final velocity of 64 m/s, we can use the kinematic equation which relates acceleration, initial velocity, final velocity, and time:

Final velocity (v) = Initial velocity (u) + (Acceleration (a) × Time (t))

Since the car starts from rest, the initial velocity (u) is 0 m/s. Using the given acceleration (a) of 3.2 m/s² and the final velocity (v) of 64 m/s, we can solve for time (t).

64 m/s = 0 m/s + (3.2 m/s² × t)

Now, we rearrange to solve for time (t):

t = (64 m/s) / (3.2 m/s²) = 20 s

Therefore, it will take the car 20 seconds to accelerate from rest to 64 m/s, which corresponds to option (b).

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