Question

Explain kirchoffs 1st and 2nd
pls give relevant answer​

Answer 1

Kirchhoff's first rule—the junction rule. The sum of all currents entering a junction must equal the sum of all currents leaving the junction.

Kirchhoff's second rule—the loop rule. The algebraic sum of changes in potential around any closed circuit path (loop) must be zero.

Answer 2

Answer:

1) Kirchoff's first law :

• Junction Law is also known as Kirchhoff’s First Law.
• It states that at the junction, sum of current entering the junction is equal to the sum of current leaving the junction.
• Junction is any point in the circuit.
• Consider a case where I1 and I2are the currententering the junction and,currentI4 and I5 are exiting out of the junction.
• According to Kirchhoff’s law; I₁+ I₂ =I₃+ I₄+ I₅ [See attachment]

2) Kirchoff's second law :

• Loop law is also known as Kirchhoff’s Second Law.

• It states that in a closed loop,algebraic sum of Emfsis equal to the algebraic sum of product of resistances and respective currents flowing through them.

• Consider a simple circuit havingEmfs = E1 and E2; R1 and R2 = resistances; current =I1 and I2.

• Then according to this law : E1+E2=I1R1+ I2R2
• For example:-
• Consider given figure,let Emfs be E1 and E2 internal resistances be R1, R2 and R3.
• Steps to use Kirchhoff’s law:-
• Choose the loop to apply Kirchhoff’s law.
• Assume any direction.
• Emf is +ive if assumed direction leaving +ive terminal of battery.
• IR is +ive if the current in the assumed direction.
• Consider closed loop ABCDFA, using the assumptions;
• E2=+R2I3 +R3I2 ;where I3=current flowing through R3
• Closed loop FCDEF, +E1= +I1R1 + I3R2
• Closed loop ABDEA, -E1 + E2 = -I1R1 +I2R3
• If the direction of current is taken opposite then
• Closed loop ABCDFA ;- -E2=-R2I3-R3I2
• FCDEF; -E1= -I1R1 - I3R2
• ABDEA; +E1 - E2 = +I1R1 -I2R3

[See attachment]

Hope it helps!!