Your story has to include one part of constant forward motion, one part of constant backward motion and a period of stationary. For the part of forward motion, it has at least to be 10 seconds time duration with a minimum of 100 meter in length. For the part of backward motion, it must be at least 5 seconds time duration with a minimum of 50 meter in length. The object has to stop at least for 5 seconds during the direction changes. During the whole motion, the object has to stay on a straight line. (10 points)

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)

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground.what is his gravitational potential energy above the ground?

Observations show that interstellar clouds can have almost any shape and