Question

A battery of 12V is connected to a series combination of resistors 3 ohm , 4 ohm , 5 ohm and 12 ohm . How much current wud flow thru de 12 ohm resistor?

Answer 1

Total resistance

3+4+5+12 = 24 Ω

R = V/I
24 = 12/I

I = 12/24 = 1/2 = 0.5 A

So we know that current flowing in series is same in every resistor

so the current flow through the resistor of 12 ohm will be 0.25 ohm.

Answer 2

0.5 A current passes through the 12Ω resistor.

Given,

12V battery connected across

a combination of resistors

$R_1$ = 3Ω

$R_2$ = 4Ω

$R_3$ = 5Ω

and $R_4$ = 12Ω

connected in series.

To find,

The current $I$ passing through $R_4$

Solution,

Total resistance in circuit $R_{eq$ = $R_1$ + $R_2$ + $R_3$ + $R_4$   (∵ all are in series)

we know that V = IR

where V is the potential difference

I is the current and R is the resistance.

So, the amount of current passing through $R_4$ can be found using the equation,

V = $IR_{eq$   (we know current remains the same throughout the circuit.)

⇒$I_$ = V/$R_{eq$

⇒$I_$ = 12/25 = 0.5 A

∴ The current passing through $R_4$ is 0.5 A.