Question

When unequal resistors are connected in parallel in a circuit:

A) the largest resistance has the largest current through it.

B) the potential drop is always the same across each resistor.

C) the same current always runs through each resistor.

D) the power generated in each resistor is the same.

Answer 1

B) the potential drop is always the same across each resistor

Step-by-step explanation:

Resistors are said to be in parallel if they are connected in different branches, and the end of each branch corresponds to the end of the other branches: so that, they are connected to points at same voltage. So, resistors in parallel have the same potential drop across them.

Therefore, we can analyze each statement:

A) the largest resistance has the largest current through it. --> FALSE. The current through each resistor is given by Ohm's law:

`I=(V)/(R)`

where V is the potential drop and R the resistance. As we see, since the voltage is constant, the larger the resistance, the less the current.

B) the potential drop is always the same across each resistor. --> TRUE, for what we said above.

C) the same current always runs through each resistor. --> FALSE, for what we said in part A.

D) the power generated in each resistor is the same. --> FALSE. The power dissipated in each resistor is

`P=(V^2)/(R)`

where V is the voltage and R the resistance; the voltage is the same for all resistors, however the resistance is not, so the power dissipated is not the same.