Question

A charge of `9 C` is passing through points A and B on a circuit. If the charge's electric potential changes from `21 J` to `12 J`, what is the voltage between points A and B?

Answer 1

`V_"AB"=-1 " V"`

Explanation:

`Delta W=q(V_B-V_A)`
`"it is done work ; if a charge is gone from one point to another"`
`V_B-V_A=V_"AB" " we can write"`
`Delta W=q*V_"AB"`
`Delta W=W_B-W_A`
`Delta W=12-21=-9 " J"`
`-9=9*V_"AB"`
`V_"AB"=-1 " V"`