Electric Potential

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Electric Potential at a point in an electric field is the work done per unit charge by an external agent in bringing a positive test charge from infinity to that particular point without acceleration.

• E-field lines always point from region of high potential(+) to regions of low potential (-)
• Unit: Volts (V)

Various equations for electric potential:

$$V = \frac{W}{q}$$

, where

• V is electric potential,
• W is work/energy,
• q is charge

$$V = \frac{Q}{4 \pi \epsilon_{o} r}$$

, where

• V is electric potential,
• Q is charge,
• r is distance from the charge

$V = Er$

, where

• V is electric potential,
• E is electric field,
• r is distance from the charge

Electric potential of a positive charge decreases with increasing r.

Electric potential of a negative charge increases with increasing r.