Light incident on a polarizer is then passed through a second polarizer. if the polarizer and the analyzer are perpendicular to each other, what can you say about the light waves emerging from the second polarizer?

Intensity of light emerging from second polarizer will be ZERO.

Explanation:

When an unpolarized light will pass through the polarizer then its components of oscillating magnetic field and electric field is confined in a plane, this phenomenon is known as polarization.

So in this phenomenon the other components of the field which is out of the plane is completely removed from the light and this will reduce the intensity of light after polarization.

Now when this polarized light passed through another analyzer then in this case if the axis inclined at some angle then light intensity will again changed by Law of Malus as

now it is given here that angle here between the two axis is 90 degree as analyzer is placed perpendicular to polarizer

So here we will have

so we will have no light light coming out of the analyzer if it is perpendicular to polarizer axis

i think the answer would be b

conservation of mass

mass before something happens = mass afterwards