A student is using a 68 ohm resistor to build a circuit with a voltage source. If the student needs 0.72 amperes of current to flow through the resistor, what voltage should be used?

48.96V

Explanation:

Given parameters:

Resistance  = 68Ω

Current  = 0.72A

Unknown:

Voltage  = ?

Solution:

According to ohm's law;

           V = IR

V is the voltage

I is the current

R is the resistance

  Now insert the parameters and solve;

      V  = 68 x 0.72 = 48.96V