Two questions plz help.

1. Linearly polarized light has an electric field with an amplitude E. The electric field is aligned horizontally and is incident on a polarizer that has its transmission axis at 50 degrees from the horizontal. What is the amplitude of the electric field after the polarizer and what is the corresponding intensity?

2. We wish to use a 45-45-90 degree prism to totally internally reflect light. What is the Minimum refractive index that the glass must have in order for this to work?

If this minimum refractive index corresponds to the refractive index of the glass for blue light, will red light also be totally internally reflected? )explain reasons in one sentence)

Thank you very much, its really urgent... PLZ help, appreciation!

can someone help plz?

Please post your attempt or specific difficulty.
Check out your reference text, class notes etc. and i am sure you will find useful stuff there, because these problems seem straightforward.

You could also look thru the threads in the optics sections. There are problems on polarization, total internal reflection etc which can give you a push in the right direction.