Conservation of Charge
Physics: IB Diploma Higher Level, topic 4.5.2
Conservation of Charge
Charge is a conserved quantity in all interactions.
Conservation of charge
- The law of conservation of charge states that the total charge is constant in any process.
Amber and cloth
- Both amber and cloth are originally neutral, with equal positive and negative charges.
- When rubbed together, some negative charge is transferred to the amber, leaving the cloth with a net positive charge.
- When separated, the amber and cloth now have net charges, but the absolute value of the net positive and negative charges will be equal.
Particle accelerators
- In particle accelerators, mass can be created from energy in the amount .
- Whenever a charged particle is created, another with opposite charge is always created along with it, so that the total charge created is zero.
- Usually, the two particles are “matter-antimatter” counterparts, like an electron and a positron.
Test yourself on Conservation of Charge
A glass rod that is initially neutral is rubbed with a silk cloth and has a charge of +5e. What is the charge on the silk cloth?
A hydrogen atom has a nucleus with charge +1e and an electron orbiting with charge -1e. What is its overall charge?