Four oranges were placed in a series circuit. Approximately what voltage did this produce?

Four times the original amount if only one orange was used

Explanation:

We can assume that the oranges all have equal voltages. Connecting them in series will have an increasing effect on the voltage delivered. In our case, this will produce 4 times the voltage of the circuit when only one orange is used.

Whenever simple cells are connected in series, the voltages of the individual cells are added up to form the voltage of the whole circuit.

Let us assume that the voltage of each of the oranges is approximately 0.9 volts. The Voltage produced when the 4 oranges are joined in series is 0.9 + 0.9 + 0.9 + 0.9 = 3.6 volts