Question
a.) The largest pushing force that can be applied before the crate starts moving is of size:
N
b.)-d.) If the pushing force were instead the two amounts shown below, please fill in the rest of the values on the chart below:
friction force: (size only)
(indicate static or kinetic):
horizontal pushing force: friction force: (size only)
(indicate static or kinetic):
net force on crate: (size only)
acceleration of crate: (size only)
9 N N, ---Select--- static kinetic N m/s2
120 N N, ---Select--- static kinetic N m/s2
Explanation / Answer
(a) Mass, m = 10 kg Coefficient of static friction, s = 0.6 Largest force applied = Static limiting friction = s m g = 0.6 * 10 * 9.8 = 58.8 N (b) to (d)
Horizontal pushing force = 9 N: Friction force = 9 N ( Static ) Net force = 0 N Acceleration = 0 m/s^2
Horizontal pushing force = 120 N: Friction force = k m g = 0.5 * 10 * 9.8 = 49 N ( Kinetic ) Net force = Pushing force - frictional force = 120 - 49 = 71 N Acceleration = Net force / mass = 71 / 10 = 7.1 m/s^2
Horizontal pushing force = 120 N: Friction force = k m g = 0.5 * 10 * 9.8 = 49 N ( Kinetic ) Net force = Pushing force - frictional force = 120 - 49 = 71 N Acceleration = Net force / mass = 71 / 10 = 7.1 m/s^2