Answer:
Force of Friction = -50 (N)
Acceleration = 2.45 (m/s^2)
Step-by-step explanation:
Force of Friction = f = N * coefficient of friction
N = m * g
=> Force of Friction = m * g * coefficient of friction
f = 20 * 10 * -0.25 = -50 (N)
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(1) F net = F + f
(2) F = m * a
(1) F net = 99 - 50 = 49
(2) a = 49 / 20 = 2.45 (m/s^2)