## 3.2.1.3 Lab – Ohms Law Answers – ITE v7.0

## Lab – Ohm’s Law (Answer Version)

**Answer Note**: Red font color or gray highlights indicate text that appears in the Answer copy only.

Answer the following questions based on electricity and Ohm’s Law. Show all steps when solving problems.

**Answer Note**: Many of the formulas in this activity are beyond the scope of this course for many students. It is recommended to guide students through this activity if it will be used.

- What are the four basic units of electricity? Provide the variable name and symbol, and unit name and symbol.

Type your answers here.

Voltage (V), Volt (V)

Current (I), Amps (A)

Resistance (R), Ohms ()

Power (P), Watts (W) - Write the equation for Ohm’s Law.

Type your answers here.

V = IR - Re-arrange the Ohm’s Law equation to solve the following:

I =R =*Type your answers here.*

I = V/R R = V/I*Type your answers here.*

- Power is equal to voltage multiplied by current. Add the missing information in each of the following power equations.

P = VP = R*Type your answers here.*

P = V*Type your answers here.*

^{2}P = VI P = RI*Type your answers here.*

^{2 }P = V^{2}/R - The yellow wire connected to a power supply carries 12V. If the power supply provides 60W of power to the yellow wire, how much current is passing through the yellow wire?

Type your answers here.

I = P/V = 60W/12V = 5A - There are 3.3V passing through an orange power supply cable, and there are 0.025 ohms of resistance in the orange wire. How much power is supplied to the orange wire by the power supply?

Type your answers here.

P = V2/R = 3.3V X 3.3V/.25 = 43.56W - A wire from the power supply is carrying 120W of power and 24A of current. Which color(s) of cable is the wire?

Type your answers here.

V = P/I = 120W/24A = 5V

The wire color is either Red or White.