Q1.) Define a node and a junction. Specify the law applicable at a node and give the statement of this law.

Ans. A node is that point in the circuit which has two elements of the circuit meeting.

Whereas a junction is a point in the circuit where three or more elements of the circuits are meeting.

The elements can be active as well as passive.

The law applicable at the node is KCL.

KCL states that the algebraic sum of all the currents in a circuit is equal to zero.

OR

The currents entering a junction is equal to the currents leaving the junction.

Q4.) Mention similarities and dissimilarities between magnetic and electrical circuits.

Ans. Similarities

Electrical Circuit Magnetic Circuit

It is a closed circuit and current(I) flows throughout the circuit. It is a closed circuit and flux(?) flows throughout the circuit.

There is flow of current

I=emf/R There is flow of flux

?=mmf/S

Here emf is the circuit driver. Here mmf is the circuit driver.

Resistance R=?*l/a Reluctance S= l/µ*a

Rs=R1+R2+R3+……. Rn Ss=S1+S2+S3+……. Sn

1/Rp=1/R1+1/R2+1/R3+…..1/Rn 1/Sp=1/S1+1/S2+1/S3+…..1/Sn

Current density J=I/a Flux density B=?/a

Dissimilarities

Electric Circuit Magnetic Circuits

The current could not flow through air. The flux can flow through air.

Current actually flows the circuit. Flux doesn’t actually flow in the magnetic circuit.

Current is reduced to zero after the removal of emf. Flux is reduced to zero after the removal of mmf.

Q2.) Two resistances of equal values when placed in parallel gives an effective resistance equal to R. What will be the effective resistance if the two resistances are connected in series?

3556049783900Ans.

Q3.) In the network given in Fig., determine current i.

Ans.