# Calculation of current in circuit

As per below image of circuit one resistor R1 connected in series & Two resistor R2, R3 are connected in parallel .

As per Ohm’s Law Formula:

I = V / RT

As per circuit first we need to calculate the total resistance.

Parallel resistance formula:

Rp = R2 X R/ R+ R3

Rp = 20 X 30 / 50

Rp = 12 E

Now we will calculate the total resistance as per series resistance formula .
RT = R1 + RP
RT = 10 + 12 = 22 E
Now we will calculate the current as per OHM’s Law.
I = V / RT
I = 9 / 22 = 0.409 A

# Calculation of voltage drop in circuit

As per below image of circuit have one battery & two resistor R1 & R2 connected in series.

As per circuit first we need to calculate the total resistance.

Series resistance formula:

RT = R1+ R2

RT = 2 + 3

RT = 5 E

As per Ohm’s Law Formula:

I = V / RT

V = I RT

20 = I 5

I = 20/5 = 4A

Now first we will calculate the voltage drop across the R1.

V1 = IXR1

V1 = 4 X 2 = 8 V

Now first we will calculate the voltage drop across the R2.

V2 = 4 X 3 = 12 V

As per new circuit if three resistor are connected in series.

Series resistance formula:

RT = R1+ R+ R3

RT = 3 + 4 + 5

RT = 12 E

As per Ohm’s Law Formula:

I = V / RT

V = I RT

36 = I 12

I = 36/12 = 3A

Now first we will calculate the voltage drop across the R1.

V1 = IXR1

V1 = 5 X 3 = 15 V

Now first we will calculate the voltage drop across the R2.

V2 = 4 X 3 = 12 V

Now we will calculate the voltage drop across the R3.

V2 = 3 X 3 = 9 V