A 25.0 Kg box is being pushed by a man horizontally. If the man applies a force of 200.0 N to keep the box moving at a constant velocity, what is the force of friction on the box? (b)
What is the μ\muμ k on the box? (Show your work)

(c)
What was the net force on the box

What is the angular momentum of the bar about the axle?

The ultracentrifuge is an important tool for separating and analyzing proteins. because of the enormous centripetal accelerations, the centrifuge must be carefully balanced, with each sample matched by a sample of identical mass on the opposite side. any difference in the masses of opposing samples creates a net force on the shaft of the rotor, potentially leading to a catastrophic failure of the apparatus. suppose a scientist makes a slight error in sample preparation and one sample has a mass 10 mg larger than the opposing sample. if the samples are 12 cm from the axis of the rotor and the ultracentrifuge spins at 70,000 rpm, what is the magnitude of the net force on the rotor due to the unbalanced samples? ( be thorough on your answer)

(1 point) match the differential equations and their vector valued function solutions. you may wish to multiply at least one solution out fully, to make sure that you know how to do it. you can get the other answers quickly by process of elimination and just multiply out one row element.