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If a cell is connected with an external resistor of 6V and a switch and a voltmeter is connected across the terminals of the cell which reads 2.6 V when the switch is open and 2.4 V when the switch is closed, how do you find the emf and the internal resistance?
so far i tried doing:
V = IR
hence 2.4/6 = 0.4 A
V = Ir
2.6/0.4 = 6.5 V
substituting the above into:
V = E - Ir
2.6 = E - (0.4 x 6.5)
E = 2.6 + (0.4 x 6.5)
therefore E = 5.2 V
but something seems very wrong here..
any help would be much appreciated =)
so far i tried doing:
V = IR
hence 2.4/6 = 0.4 A
V = Ir
2.6/0.4 = 6.5 V
substituting the above into:
V = E - Ir
2.6 = E - (0.4 x 6.5)
E = 2.6 + (0.4 x 6.5)
therefore E = 5.2 V
but something seems very wrong here..
any help would be much appreciated =)