# Worksheet: Ohm's Law

In this worksheet, we will practice defining voltage, current, and resistance and using Ohm's law to calculate these values in simple electrical circuits.

**Q1: **

Which of the following is the best definition of electrical current, as measured in amperes?

- AThe energy dissipated per electron between two given points
- BThe number of electrons that pass a given point in one second
- CThe energy dissipated by the electrons passing between two given points in one second
- DThe number of coulombs of electrons that pass a given point in one second
- EThe energy dissipated per coulomb of electrons between two given points

**Q3: **

If a redox couple is at equilibrium in an electrochemical cell, which of the following statements about the current and potential is most accurate?

- AThe potential is zero, and the current is given by the Nernst equation.
- B The current is positive, and the potential is zero.
- CThe current is zero, and the potential is given by the Nernst equation.
- DThe current is negative, and the potential is zero.
- EThe current and potential are both zero.

**Q4: **

The total current in the circuit below is 100 mA.

Calculate, to the nearest ohm, the total resistance of the parallel combination of resistors.

What is the total resistance in this circuit to the nearest ohm?

What is the voltage across the 500 Ω resistor to 2 significant figures?

What is the current in the 600 Ω resistor to the nearest milliampere?

**Q5: **

The current in the circuit shown is 100 mA.

What is the current in the 50 Ω resistor to the nearest milliampere?

What is the voltage across the 40 Ω resistor to 2 significant figures?

What is the total resistance in this circuit to the nearest ohm?

What is the voltage of the battery in this circuit to the nearest volt?