Which statement is the BEST analysis of the data for the runner? A The runner starts slower and speeds up, reaching a maximum speed between 50 and 70 m, and then slows down during the final 30 m.
B. The runner covers the first 80 m running at a constant speed and then slows down, reaching a minimum speed during the final 20 m
CO The runner starts siower and speeds up, reaching a constant speed between 20 and 80 m, and then speeds up again during the final 20 m
D. The runner covers the first 70 m running at a constant speed and then speeds up, reaching a maximum speed during the final 30 m.
no

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)