Abeam of protons moves in a circle of radius 0.23 m. the protons move perpendicular to a 0.31-t magnetic field. (a) what is the speed of each proton? (b) determine the magnitude of the centripetal force that acts on each proton.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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current flows in a wire

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