All AP Physics 1 Resources
Example Questions
Example Question #2 : Understanding Circuit Diagrams
In the circuit above, what is the total voltage?
To find the voltage, first find the combined resistances of the resistors in parallel:
Use Ohm's law to find the voltage.
Example Question #3 : Understanding Circuit Diagrams
In the circuit above, what is the resistance of ?
Find the total resistance of the circuit, which can be determined using Ohm's law.
Now, the resistance of the second resistor can be found. Since the two resistors are in parallel, they're related to the total resistance as follows:
Rearrange and solve for
Example Question #5 : Understanding Circuit Diagrams
In the circuit above, what is the total resistance?
Find the combined resistances for the resistors in parallel:
Combine these two combined series resistors to find the total resistance:
Example Question #4 : Understanding Circuit Diagrams
In the circuit above, what is the voltage drop across ?
Find the total resistance of the circuit. First, calculate the values of the combined resistances of the resistors in parallel:
Therefore, the total resistance is:
Now, note that since and are in parallel, the voltage drop across them is the same. Use Ohm's law to relate current in terms of voltage and resistance.
Substitute into Ohm's law for the resistance across :
Example Question #1311 : Ap Physics 1
In the circuit above, what is the current passing through ?
Find the total resistance of the circuit. First, calculate the values of the combined resistances of the resistors in parallel:
Therefore, the total resistance is:
From Ohm's law, we know that is the current traveling through the circuit.
This current will be divided between and , with more current taking the path of lower resistance.
Total voltage drop across :
The current through is given by:
Example Question #11 : Understanding Circuit Diagrams
In the circuit above, what is the total resistance?
Begin by combining the resistors that are immediately in series:
Now to find the total resistance, combine these two new resistance values, which are in parallel:
Example Question #11 : Understanding Circuit Diagrams
In the circuit above, what is the voltage drop across ?
To approach this problem, note that there are no other resistors (or combinations or resistors) beyond the parallel arrangement shown, so the voltage drop across the top and the bottom is the same and equal to the voltage across the circuit, .
The voltage drop across can be found as:
Example Question #12 : Understanding Circuit Diagrams
In the circuit above, what is the current passing through ?
To approach this problem, note that there are no other resistors (or combinations or resistors) beyond the parallel arrangement shown, so the voltage drop across the top and the bottom is the same and equal to the voltage across the circuit, .
Furthermore, the current that passes through must be the same as the current that passes through .
Therefore, the current that passes through them can be found by rearranging Ohm's law, solving for current.
Example Question #13 : Understanding Circuit Diagrams
In the circuit above:
What is the current across ?
The quickest way to approach this problem is to realize that the voltage drop across is the same as the voltage drop across the combined resistances of and . Since this parallel combination is the only presence of resistance in the circuit, this voltage drop must be the total voltage of the circuit, .
Therefore, the current across is:
Example Question #14 : Understanding Circuit Diagrams
In the circuit above:
What is the current across ?
Realize that the voltage drop across the combined resistances of and must be equal to the voltage of the circuit, since the parallel combination is the only presence of resistance in the circuit. This voltage drop must be the total voltage of the circuit, .
The current across and is the same, and is given as: