Answered

Consider a large 1.54 V carbon-zinc dry cell used in a physics lab to supply 2.15 A to a circuit. The internal resistance of the cell is 0.105 Ω. What is the terminal voltage, V, of the cell, in volts?

Answer :

Answer:

1.77V

Explanation:

The electromotive force voltage (E) in a cell, is related to the lost voltage ([tex]V_{L}[/tex]) and the terminal voltage ([tex]V_{T}[/tex]) as follows;

E = [tex]V_{T}[/tex] - [tex]V_{L}[/tex]

Where;

The lost voltage ([tex]V_{L}[/tex]) is the product of the internal resistance (r) of the cell and current (I) in the cell. i.e

[tex]V_{L}[/tex] =  I x r

Substitute [tex]V_{L}[/tex] =  I x r into equation (i) as follows;

E = [tex]V_{T}[/tex] - (I x r)           ----------------------(ii)

According to the question;

E = 1.54V

I = 2.15A

r = 0.105Ω

Substitute these values into equation(ii) as follows;

1.54 = [tex]V_{T}[/tex] - (2.15 x 0.105)

1.54 = [tex]V_{T}[/tex] - (0.22575)

1.54 = [tex]V_{T}[/tex] - 0.22575

Solve for [tex]V_{T}[/tex];

[tex]V_{T}[/tex] = 1.54 + 0.22575

[tex]V_{T}[/tex] = 1.54 + 0.22575

[tex]V_{T}[/tex] = 1.77V

Therefore, the terminal voltage of the cell is 1.77V

Other Questions