The following figure shows a network of currents, their magnitudes and directions. The current Iwill be equal to _____.
A
−3A
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
3A
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
13A
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
20A
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution
The correct option is D20A Applying Kirchhoff's first law which states that, the sum of currents entering a particular node or a junction is equal to the sum of currents leaving the same node or junction.
In the figure shown above, iA=12+8=20A -- (1) iB=iA+3=20+3=23A -- (2) iD+5=8A⟹iD=3A -- (3)
but iD=3A=iB+I=23+I -- (4)
On solving, we get I=23−3=20A.