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A 4.23 kg ball travels at 2.79 m/s across level ground against friction, where the coefficient of kinetic friction is equal to 0.156. How much time does the ball travel for before coming to a complete stop?

Respuesta :

Answer:

1.82 s

Explanation:

Newton's second law of motion says that the net force on an object is equal to the mass times acceleration, which is equal to the change in velocity over time.

Applying Newton's second law:

∑F = ma

-mgμ = ma

a = -gμ

Acceleration is change in velocity over time:

(v − u) / t = -gμ

(u − v) / t = gμ

t = (u − v) / gμ

Plugging in values:

t = (2.79 m/s − 0 m/s) / (9.8 m/s² × 0.156)

t = 1.82 s