Question

An inductor $(L=100mH)$, a resistor $(R=100Omega)$ and a battery $(E=100V)$ are initially connected in series as shown in figure. After a long time the battery is disconnected after short circuiting the points $A$ and $B$. The current in the circuit after $1m$ sec is

• A. $1A$
• B. $\frac{1}{e}A$
• C. $eA$
• D. $0.1A$

Answer 1

Answer: (A), (C)

$eA$
$1A$

Let the volume of ice-bergs is V and its density is $\rho$. If this ice-berg floats in water with volume $V_{in}$ inside it then $V_{in}\sigma g=V\rho g$
$\Rightarrow V_{in}=\left(\frac{\rho }{\sigma }\right)V$
$\Rightarrow V_{out}=V-V_{in}=\left(\frac{\sigma -\rho }{\sigma }\right)V$
$=\left(\frac{1000-900}{1000}\right)V=\frac{V}{10}$
$\Rightarrow \frac{V_{out}}{V}=0.1=10\%$.