At any given instant in time, a 4-kg rock that has been dropped from a high cliff experiences a force of air resistance of 15N.
What are the magnitude and direction of the acceleration of the rock? (don't forget gravitational force!)
Answers
Answered by
11
m = mass of the rock being dropped = 4 kg
g = acceleration due to gravity = 9.8 m/s²
W = weight of rock dropped in downward direction = mg = 4 x 9.8 = 39.2 N
f = force due to air resistance in Upward direction = 15 N
a = acceleration of the rock in down direction
taking down as the positive direction of motion and Upward direction as negative
force equation for the motion of rock is given as
W - f = m a
39.2 - 15 = 4 a
a = 6.05 m/s²
direction : downward
Similar questions