AP Physics 2 : Ohm's Law
Study concepts, example questions & explanations for AP Physics 2
All AP Physics 2 Resources
Example Questions
Example Question #21 : Circuit Properties
A single 
Use Ohm's law:
Converting 
Example Question #21 : Circuits
In the circuit above, find the current through 
None of these
First, find the total resistance of the circuit.
Next, add the series resistors together.
Use Ohm's law to find the current in the system.
The current through 
Also, the voltage drop across them need to be equal, since they are in parallel.
Set up a system of equations.
Solve.
Example Question #21 : Circuits
In the circuit diagram shown below, both resistors have a resistance of 
The current will decrease by a factor of
The current will halve
The current will double
The current will not change
The current will increase by a factor of
The current will not change
In this question, we're shown a circuit diagram with two resistors connected in parallel. We're also told that both resistors have the same resistance. We're then asked to determine how the current through one of the resistors will change if the other one is removed.
To answer this question, we'll need to take Ohm's law into account, which states the following.
Moreover, for two resistors connected in parallel, the equivalent resistance is found by summing the inverses of the individual resistors. In the event that two resistors have the same value, as in this case, the equivalent resistance will be cut in half.
Since the equivalent resistance of the circuit is half as great as either resistor, the removal of 
Now, it's important to realize that the current of the entire circuit becomes half as great. But remember that in the original circuit, the overall current (which was twice as great) was split between the two resistors. Thus, even though the overall current in the circuit is being cut in half, the entirety of the new current is flowing solely through 
Example Question #21 : Circuit Properties
You have a circuit with a 
To find the current in a circuit with a battery and resistor(s), you use Ohm's Law.
We have the voltage and we have the resistance, so we don't need to rearrange the equation.
Therefore, the current through the resistor is 2 amps (
Certified Tutor
Certified Tutor
All AP Physics 2 Resources
