Draw a free-body diagram representing each of the following objects. use the correct force labels:
a. a ball falling in the presence of air resistance
b. a helicopter lifting vertically off a landing pad, not in contact with the ground
c. an athlete running along a horizontal track

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?