A-level Physics (Advancing Physics)/Charge

Electrons, like many other particles, have a charge. While some particles have a positive charge, electrons have a negative charge. The charge on an electron is equal to approximately -1.6 x 10^-19 coulombs. Coulombs (commonly abbreviated C) are the unit of charge. One coulomb is defined as the electric charge carried by 1 ampere (amp) of current in 1 second. It is normal to ignore the negative nature of this charge when considering electricity.

We can calculate the total charge from the number of particles (eg. electrons) and the charge on each particle using the formula:

Q_total = n Q_particle

where Q = charge, and n = number of particles.

Hence:

$n=\frac{Q_{total}}{Q_{particle}}$

Questions

1. How much charge do 3024 electrons carry?

2. How many electrons does is take to carry 5 C of charge?

3. The total charge on 1 mole of electrons (6 x 10²³ particles) is equal to 1 faraday of charge. How many coulombs of charge are equal to 1 faraday?

/Worked Solutions/