(a) Applying Kirchoff's law in following figure.
At junction $A$ :
$i + {i_1} + {i_2} = 1$ .... $(i)$
For Loop $(i)$
$ - \,60\,i + (15 + 5){i_1} = 0$
$==>$ ${i_1} = 3i$ ...$(ii)$
For loop $(2)$
$-(15 + 5) i_1 + 10 i_2 = 0$
$==>$ $i_2 = i_1 = (3 i) = 6i$
On solving equation $(i), (ii)$ and $(iii)$ we get $i$ =$ 0.1\, A$
Short Trick : Branch current $=$
$\,{\rm{main current }}\left( {\frac{{{\rm{Resistance \,of \,opposite\, branch}}}}{{{\rm{Total\, resistance}}}}} \right)$
$==>$ $i = 1 \times \left[ {\frac{{\frac{{20}}{3}}}{{\frac{{20}}{3} + 60}}} \right]$
$=$ $0.1\, A$
Download our app
and get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
If a wire of resistance $20\,\Omega $ is covered with ice and a voltage of $210\, V$ is applied across the wire, then the rate of melting of ice is .................. $g/s$
In a potentiometer experiment the balancing with a cell is at length $240\, cm$. On shunting the cell with a resistance of $2$ $\Omega$, the balancing length becomes $120\, cm$. The internal resistance of the cell is ................. $\Omega $
A copper wire of length $1\, m$ and radius $1\, mm$ is joined in series with an iron wire of length $2\, m$ and radius $3\, mm$ and a current is passed through the wires. The ratio of the current density in the copper and iron wires is
To measure the internal resistance of a battery, potentiometer is used. For $\mathrm{R}=10 \Omega$, the balance point is observed at $\ell=500 \mathrm{~cm}$ and for $\mathrm{R}=1 \Omega$ the balance point is observed at $\ell=400 \mathrm{~cm}$. The internal resistance of the battery is approximately :
The length of a metallic wire is increased by $20 \%$ and its area of cross section is reduced by $4 \%$. The percentage change in resistance of the metallic wire is $.......$