One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face forms an image 12 cm behind the silvered face. The refractive index of the glass is

One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face forms an image 12 cm behind the silvered face. The refractive index of the glass is

A) 0.4     B) 0.8    C) 1.2     D) 1.6

12P02 Electric Potential and Capacitance

Understand how much distance I have to move to cause a voltage difference of 1 V 

a) Far away from the source charge b) Very close to the source charge. 

Connect that finding with Conservative Force / Field concepts

$E= - \frac{dV}{dr} \; \;  F = -\frac{dU}{dr}$

Equipotential Lines for two charges separated by a distance 

a) oppositely charged b) same charged

 

Capacitor Basics

Change the battery voltage and see what happens to 

the charge and the voltage in the capacitor, Q = C V

Change the area and gap between the plates and see what happens 

to the Capacitance value, C = epsilon_o A / d

12P07 Alternating Current

  

Virtual Oscilloscope to try different waveforms and also to input your own voice.

From the seconds/div calculate the frequency of the wave and double check the value.

What is the formula or relation between time period, frequency, angular frequency?

In a double slit experiment two coherent beams have slightly different intensities I and $\delta I$. Show that the resultant intensity at the maxima is nearly 4I, while that at the minima is $(\delta I)^2/4I$

In a double slit experiment two coherent beams have slightly different intensities I and $\delta I$. Such that I >>$\delta I$. Show that the resultant intensity at the maxima is nearly 4I, while that at the minima is $(\delta I)^2/4I$

Courtesy:ophysics.com

For Intensity at Maxima,

\[ I=I_1+I_2+2\sqrt{I_1 I_2}\cos\phi \]

\[I_{max}=I+\left(I+\delta I\right)+2\sqrt{I(I+\delta I)}\cos 0\]

\[=2I+\delta I+2I\left(1+\frac{\delta I}{I}\right)^{\frac{1}{2}}\]

\[=2I+\delta I+2I\left[1+\frac{1}{2}\frac{\delta I}{I}+\frac{\frac{1}{2}.\frac{-1}{2}}{2}\left(\frac{\delta I}{I}\right)^2\right]\]

Using Binomial theorem, ignoring the higher order terms, $(\frac{\delta I}{I})^{2}$

\[=4I+2\hspace{2mm}\delta I\]

\[\approx4I\]

FAQs by parents for Physics Class

"Teacher does not teach. 

   Student learns. 

   Teacher just helps in the process of learning."

Frequently asked questions for Physics Class

1) Sir, we heard you have stopped taking class. Are you by any chance taking classes?

Due to some throat pain issues, I took a break from classes from March 2024 to Sep 2024. Even now beyond 45 min, I am not able to speak comfortably, especially physics being a subject where one has to speak and explain a lot. So I am teaching few students coming to my home.