An atom Y has atomic number 15. It accept three electrons in order to become stable. Determine the I. Number of protons ii. Number of electrons after accepting electrons iii. Charge on the atom before accepting electrons iv. Charge on the atom after accepting electrons.

Unpolarized light falls on two polarizer sheets whose transmission axes are at right angles. a third polarizer is placed between the first two so that its axis makes a 52-degree angle with the axis of the first polarizer. a) what fraction of the incident light intensity is transmitted through the first polaroid? b) what fraction of the incident light intensity is transmitted through the second polaroid? c) what is the angle of polarization of the light that enters the third polaroid? d) what fraction of the incident light intensity is transmitted through the third polaroid. e) what happens if the middle polaroid is removed?