• The terminals of a cell make one end of the circuit?positive?and the other?negative
• This sets up a?potential difference?across the circuit
  • This is sometimes known as the?voltage

   

• Potential difference is defined as:

The amount of energy transferred per unit of charge?passing through the terminals

• This means that one?volt?(the unit of potential difference) is equivalent to one?joule?(the unit of energy) per?coulomb?(the unit of charge):

1 V = 1 J / C

• The equation linking the energy transferred, voltage and charge is given below:

• Where:
  • V =?potential difference, measured in?volts?(V)
  • E =?energy transferred, measured in?joules?(J)
  • Q =?charge moved, measured in?coulombs?(C)

   

• This can be rearranged using the formula triangle below:

Step 1: List the known quantities

• • Voltage,?V =?6 V
  • Charge,?Q?= 4200 C

   

Step 2: State the equation linking potential difference, energy and charge

• • The equation linking potential difference, energy and charge is:

   

E = V × Q

Step 3: Substitute the known values and calculate the energy transferred

E =?6 × 4200

E?= 25 200 J

• • Therefore,?25 200 J?of energy is transferred in the lamp