Electricity and Circuits Unit Test
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Question
What is the resistance of resistor R1?
A parallel circuit with a power source of 15 volts and a total current of 5 amps. The current is split through two resistors. Resistor 2 receives a current of 3 amps and resistor 1 receives an unknown current.
(1 point)
Responses
5.0 Ω
5.0 Ω
7.5 Ω
7.5 Ω
3.0 Ω
3.0 Ω
2.0 Ω
We can use Ohm's Law to find the resistance of resistor R1. Ohm's Law states that resistance (R) is equal to voltage (V) divided by current (I), or R = V/I.
In this case, the total current (I) of the circuit is 5 amps, and resistor 2 receives a current of 3 amps. So the remaining current for resistor 1 can be found by subtracting the current for resistor 2 from the total current: 5 amps - 3 amps = 2 amps.
The voltage (V) of the circuit is 15 volts.
Plugging in these values into Ohm's Law, we get:
R1 = V/I
R1 = 15 volts / 2 amps
R1 = 7.5 Ω
Therefore, the resistance of resistor R1 is 7.5 Ω.