Carbon, silicon and germanium have four valence electrons each. These are characterised by valence and conduction bands separated by energy band gap respectively equal to \((E_g)_C, (E_g)_{Si}\) and \((E_g)_{Ge}\). Which of the following statements is true?
\((E_g)_{Si} < (E_g)_{Ge} < (E_g)_C\)
\((E_g)_C < (E_g)_{Ge} > (E_g)_{Si}\)
\((E_g)_C > (E_g)_{Si} > (E_g)_{Ge}\)
\((E_g)_C = (E_g)_{Si} = (E_g)_{Ge}\)
For given three elements, he energy band gap of carbon is the maximum and that of germanium is the least. The energy band gap of these elements are related as:\( (E_g)_C > (E_g)_{Si} > (E_g)_{Ge}\)
Therefore, the correct statement is (c).
The graph shows the variation of current with voltage for a p-n junction diode. Estimate the dynamic resistance of the diode at \( V = -0.6 \) V.

“One of these days you’re going to talk yourself into a load of trouble,” her father said aggressively. What do you learn about Sophie’s father from these lines? (Going Places)
Write a letter to the editor of a local newspaper expressing your concerns about the increasing “Pollution levels in your city”. You are an environmentalist, Radha/Rakesh, 46, Peak Colony, Haranagar. You may use the following cues along with your own ideas: 
Semiconductors are a crystalline solid materials, whose electrical conductivity lies between a conductor and an insulator. Semiconductors are mainly used in the manufacturing of electronic devices like capacitors, transistors, diodes, Integrated circuits, etc.