Which two forces pull electrons toward the nucleus in an atoma. the speed of the electron and the charges of the proton and electronb. gravity and centrifugal forcec. the charges if the proton and electron and gravity

To create electromagnetic induction, which of the following has to move? a. a wire b. a magnet c. a transformer d. either a or b

Could someone . i have tried to solve myself but my calculation is off

An ideal polarizer with its transmission axis rotated 30 degrees to the vertical is placed in a beam of unpolarized light of intensity 10w/m^2. after passing through the polarizer, what is the intensity of the beam? a. 8.7 w/m^2 b. 7.5 w/m^2 c. 5.0 w/m^2 d. 10 w/m^2 e. 2.5 w/m^2