A straight vertical line with three horizontal lines at the bottom represents an earth electrode. The electrode is a conductor of electricity such as a metal plate or water pipe, partially buried in the earth to create a circuit path to the ground.
A rectangle with horizontal lines on either side or a wavy line with sharp edges act as a resistor. A resistor is a component that restricts the flow of current. A diagonal line crossing through the resistor symbol transforms it into a rheostat — a variable resistor. A rectangle with a horizontal line cutting through from end to end represents a fuse. A fuse is a protective device with a circuit opening that breaks during current overflow.
A symbol of a capacitor comprises two adjacent T-lines facing opposite directions. Capacitors store charge and consist of one or more pairs of conductors separated by an insulator. They act as filters and can block direct current while allowing alternating current to flow in the circuit. Two parallel long and short vertical lines indicate a cell, which supplies power to the circuit.
A circle with the letter A inside represents an ammeter. A circle with V inside denotes a voltmeter, and one with an arrow indicates a galvanometer. An ammeter and voltmeter measure current or voltage passing through the circuit at a particular point respectively. A galvanometer measures very small currents, often less than a milliampere. A straight line indicates a wire. It connects one component to another.