Aball is dropped from an upper floor, some unknown distance above your apartment. as you look out of your window, which is 1.50 m tall, you observe that it takes the ball 0.210 s to traverse the length of the window. 1)determine how high above the top of your window the ball was dropped. ignore the effects of air resistance. (express your answer to three significant figures.)

Anybody wanna ? (picture included? )

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)

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up