# A charge of 12 C is passing through points A and B on a circuit. If the charge's electric potential changes from 70 J to 34 J, what is the voltage between points A and B?

Jul 20, 2017
• Lets see what information we have :

• Charge (C)$= 12 C$

• At $\textcolor{b l u e}{A}$, eletric potential energy ($E$) $= 70 J$

• At $\textcolor{red}{B}$, electric potential energy ($E$) $= 34 J$

• Change in $E$$= 70 J - 34 J$$= 36 J$

• Formula relating those informations $\rightarrow$$\textcolor{g r e e n}{E} =$Charge (C)$\cdot$potential difference (V)

• Therefore,
$E = C \cdot V$
$36 = 12 V$
$12 V = 36$
$V = \frac{36}{12}$$= 3 V$$\leftarrow$