Class 11 & 12 CBSE Physics Handbook

Class 11 & 12 CBSE Physics Handbook
CBSE NEET JEE

RC Charging circuit - Transient Currents

"Nature is written in the language of Mathematics"

RC charging circuit shown here with 
Battery emf 2.35V, Resistance R=2.1 k$\Omega$, Capacitance C=10,000 $\mu F$




Voltage across the capacitor was recorded and plotted against time in sec.
Experimental data vs. Mathematical model are plotted in the graph.

Mathematical model $V=V_o (1-e^{\frac{-t}{RC}})$
We can see that the experimental values are very well matching with the mathematical model. 
It is true that "Nature is written in the language of Mathematics". 

Calculations: 
Time Constant, $\tau=RC = 2.1 \times 10^3 \times 10,000 \times 10^{-6} = 21 \hspace{2mm}sec$
$63.2\% \hspace{2mm}of \hspace{2mm}Vo = 63.2\% \hspace{2mm} of \hspace{2mm}2.35 = 1.45 \hspace{2mm}V$

We can also learn from this graph that, 
as R and C increases , time constant also increases, so it takes a long time for the voltage in capacitor to reach the maximum value. 
As and R and C decreases, time constant decreases, the graph will rise steeply reducing the time of charging.



Change the resistance value R and the Capacitance value C in the slider
to study how the curve changes, 
to observe how quickly charging and discharging are happening,
to understand what is the time constant.







Pages 134-135 from Handbook copied to show the related theory and concepts.

No comments:

Post a Comment

Please provide your valuable feedback. Students, Parents, Teachers.

Visitors

Teachers, Students, Parents can Contact Author

Name

Email *

Message *