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What is the conversion factor between kg/m^3 and g/m^3. express your experimental values for the densities in kg/m^3.

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?

Acircular ring of charge with radius b has total charge q uniformly distributed around it. what is the magnitude of the electric field at the center of the ring? 0 keq/b2 keq2/b2 keq2/b none of these answers