Question

Consider the resistances of short and open circuits. Fill in the blanks: The voltage across a short circuit will always be ______________ The voltage across an open circuit will always be ______________

Answer 1

Answer:

a) Zero

b) power source

Explanation:

According to Ohm's law, the voltage dropped in a resistance is proportional to the current flow and the resistor opposing to it.

$V=I*R$

For the case of a short circuit, the resistance tends to zero, so the voltage will tend to zero too.

In the case of the open circuit, the resitance will tend to infinity, because we cannot obtain an infite voltage, it will be limited by the power source.