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If the earth were not having atmosphere, its temperature
If the Earth did not have an atmosphere, it would not be able to trap heat from the sun effectively. The atmosphere acts as an insulating layer that helps to retain heat. Without it, the Earth's surface would lose heat quickly, leading to a much lower temperature.
_________ is responsible for the green house effect
The greenhouse effect is primarily caused by the absorption and emission of infrared radiation by greenhouse gases in the Earth's atmosphere. These gases include carbon dioxide, methane, and water vapor, which trap heat and keep the planet warm.
The dimensional formula of energy density is
Energy density is defined as the amount of energy stored in a given system or region of space per unit volume. The dimensional formula for energy is $ML^2T^{-2}$. Since energy density is energy per unit volume, we divide by volume, which has the dimensional formula $L^3$. Therefore, the dimensional formula of energy density is $\frac{ML^2T^{-2}}{L^3} = ML^{-1}T^{-2}$.
C, Si and Ge have same no. of valence electrons. C is an insulator because energy required to take one electron out from
Carbon (C) is an insulator because the energy required to excite an electron from the valence band to the conduction band is much higher in carbon than in silicon (Si) or germanium (Ge). This means that fewer electrons are available for conduction in carbon compared to silicon and germanium.
Ionization energy of isolated phosphorous atonis 10 eV. Ionization energy of same atom in Si is nearly________- eV (Relative Permitivity of silicon = 12)
Out of 5 valence electrons of phosphorous, 4 are shared with Si. Fifth electron can be approximated to revolve around nucleus. Situation is like H-atom $ En \approx -13.6 /n^2 ev $ for n = 1 , EN = -13.6 ev $E inside lattice = { En \over \epsilon_1^2 } = { -13.6 \over 12^2} =0.1 ev $
By adding impurity in intrinsic semiconductor P type semiconductor is made. Charge of these P type semiconductor is
A P-type semiconductor is created by doping an intrinsic semiconductor with a trivalent impurity (such as boron). This leads to the creation of 'holes' which can accept electrons. However, the overall charge of the P-type semiconductor remains neutral because the number of positively charged holes is balanced by the number of negatively charged electrons.
Strong overlaping of different atomic orbitals makes
Strong overlapping of different atomic orbitals in a solid leads to the formation of energy bands. These energy bands are crucial in determining the electrical properties of materials, such as whether they behave as conductors, semiconductors, or insulators.
We can not make p-n junction diode by making P type semi-condutor join with N - type semi-conductor, because
For p-n junction, which statement is incorrect
The intrinsic semi-conductor has :
An intrinsic semiconductor has a finite resistance that decreases with temperature. As temperature increases, more electron-hole pairs are generated, thereby increasing the number of charge carriers and decreasing the resistance.
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The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.