The actual speed of electrons drifting along in a common electric circuit is about the speed of which of the following?. A) sound.B) a fast-moving automobile.C) light.D) a slow-moving snail.

D. Do the numbers.

Divide the current in Amperes by the electron charge, the free electron density, and the wire cross sectional area.

V = I/(nAe)

The actual speed of electrons drifting along in a common electric circuit is much slower compared to the speed of sound, a fast-moving automobile, or light. It can be better compared to the speed of a slow-moving snail.

To understand why, let's delve into some basic physics. In an electric circuit, when you turn on a switch or plug in a device, the voltage difference (provided by a power source like a battery or generator) creates an electric field. This electric field exerts a force on charged particles, such as electrons, present in the circuit.

The actual speed at which electrons move, known as the drift velocity, is quite slow. It typically ranges from a few millimeters per second to a few centimeters per second. This is because electrons experience collisions with other particles in the conductor, impurities, and lattice vibrations, which hinder their movement.

However, despite the slow individual speed of electrons, electric current can propagate at high speeds along the circuit. This is because electrical energy is transferred through the movement of charge rather than the movement of individual electrons. When a voltage is applied across a conductor, electrons closer to the voltage source are repelled, and these electrons repel the ones nearest to them, creating a chain reaction that results in the transfer of energy throughout the circuit.

So, to answer the question, the actual speed of electrons drifting along in a common electric circuit is similar to the slow-moving snail (option D).