sketch a position versus time (position-time or x-t) graph and a velocity versus time (v-t) graph for each of the following scenarios (assume right is positive at a constant velocity)

Which statement best describes resistance? resistance is a. how well a current will flow in a material and is measured in volts. b. how well a material conducts an electrical charge and is measured in ohms. c. the ability of a material to attract a positive charge to create a current. d. the ability of a material to repel neutral charges and is measured in ohms.

Suppose that a comet that was seen in 563 a.d. by chinese astronomers was spotted again in year 1951. assume the time between observations is the period of the comet and take its eccentricity as 0.986. what are (a) the semimajor axis of the comet's orbit and (b) its greatest distance from the sun?

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)