What does it mean for electric charge to be quantized?

What does it mean for electric charge to be quantized?

• A. It can take any real number
• B. It comes in discrete, countable amounts
• C. It is always negative
• D. It changes randomly

Answer: (B)

Quantized charge means charge comes in fixed steps rather than any possible value. The fundamental unit is the elementary charge, e ≈ 1.6 × 10^-19 coulombs, so the net charge of any object is an integer multiple of e (such as -2e, -e, 0, +e, +2e, and so on). This is why individual particles like electrons and protons carry exact charges and why you don’t observe a single particle with a fraction of an elementary charge. In everyday objects, many charges add up to a net charge that is still a multiple of e. The idea that charge can be any real number or that it must always be negative or change randomly doesn’t align with the fact that charge comes in these discrete, countable units.

Quantized charge means charge comes in fixed steps rather than any possible value. The fundamental unit is the elementary charge, e ≈ 1.6 × 10^-19 coulombs, so the net charge of any object is an integer multiple of e (such as -2e, -e, 0, +e, +2e, and so on). This is why individual particles like electrons and protons carry exact charges and why you don’t observe a single particle with a fraction of an elementary charge. In everyday objects, many charges add up to a net charge that is still a multiple of e. The idea that charge can be any real number or that it must always be negative or change randomly doesn’t align with the fact that charge comes in these discrete, countable units.