Q. Two packages at UPS start sliding down the 20 ^circ ramp shown in the figure. Package A has a mass of 4.00 kg and a coefficient of kinetic friction of 0.220. Package B has a mass of 10.5 kg and a coefficient of kinetic friction of 0.150.
How long does it take package A to reach the bottom?
Q. A fan blade, initially at rest, rotates with a constant acceleration of 0.025 rad/s2. What is its angular speed at the instant it goes through an angular displacement of 4.2 rad?