Which of the following is an accurate statement?

a. step-up voltage transformers have a lower number of turns in the primary than in the secondary winding.
b. dc generators produce current with a voltage that changes from positive to negative.
c. step-down voltage transformers have a different number of turns in the primary than in the secondary winding, so they change the incoming voltage to a higher voltage.
d. ac generators produce current that is pulsating, but always remains positive.

It may seem strange that the selected velocity does not depend on either the mass or the charge of the particle. (for example, would the velocity of a neutral particle be selected by passage through this device? ) the explanation of this is that the mass and the charge control the resolution of the device--particles with the wrong velocity will be accelerated away from the straight line and will not pass through the exit slit. if the acceleration depends strongly on the velocity, then particles with just slightly wrong velocities will feel a substantial transverse acceleration and will not exit the selector. because the acc