When two alternating quantities of the same frequency have different zero points, they are said to have a phase difference. The angle between zero points is the angle of phase difference φ. In the above-given question, the frequency of voltage and current is different so we can’t calculate the phase difference between them
In the PMMC type instrument, the deflection is directly proportional to the current flowing through the instrument, we get a uniform scale for the instrument. It gives a uniform scale of upto 270° or more. Td ∝ I
Phosphorus (P) has 15 electron i.e 2,8,5. Hence the number of electron in its outermost orbit is 5. Silicon (Si) has 14 electron i.e 2,8,4. Hence the number of electrons in its outermost orbit is 4.