Suppose you have 4 stars with given initial conditions (positions and momenta). the net force on each star is the vector sum of 3 forces exerted by the other 3 stars, for a total of 12 forces that must be evaluated in each iterative step. in each step, how many forces would you have to calculate fully, and how many forces could you calculate simply by reversing vectors already calculated?

Frost wedging occurs when water seeps into a crack in a rock, freezes, and causes the crack in the rock to widen. t or f

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)

Select all that applywhat are some basic resources a family is expected to provide for children? educationclothesspending