As per analysis for previous years, it has been observed that students preparing for NEET find Physics out of all the sections to be complex to handle and the majority of them are not able to comprehend the reason behind it. This problem arises especially because these aspirants appearing for the examination are more inclined to have a keen interest in Biology due to their medical background.
Furthermore, sections such as Physics are dominantly based on theories, laws, numerical in comparison to a section of Biology which is more of fact-based, life sciences, and includes substantial explanations. By using the table given below, you easily and directly access to the topics and respective links of MCQs. Moreover, to make learning smooth and efficient, all the questions come with their supportive solutions to make utilization of time even more productive. Students will be covered for all their studies as the topics are available from basics to even the most advanced.
(c) In forward biasing of PN junction diode width of depletion layer decreases. In intrinsic semiconductor fermi energy level is exactly in the middle of the forbidden gap
(b) In a p-n junction diode, electrons in conduction band on n-type side travel across the junction and leave the positively ionized impurity atoms unneutralised. Consequently, there is positively charged region adjacent to the junction in n-type material. On p-type side the electrons which have traversed the boundary recombine with positive holes in the valence bandand form a layer of unneutralised negatively ionised trivalent impurity atoms making a negatively charged region as shown in figure. The region around the junction is called charge depletion region or space charge region. Hence, within the depletion region, p-side is negative and n-side is positive.
(D)
Q4. In an unbiased p-n junction
(b) Graph between potential and distance in a p-n junction diode is given by ∴potential at p is less than that at n.
(a) I2/I1 =(V2/V1 )^(3/2) orI2=I1 (V2/V2)3/2 =80(400/200)^(3/2)=80×2√2=160√2
(C)
(D)
(a) Lower NOT gate inverts input to zero. NOT gate from NAND gate inverts this output to 1 upper NAND gate converts this input 1 and input 0 to 1. Thus A=1 and B=1 become inputs of NAND gate giving final output as zero. Choice A is correct
(c) (b) The electric resistance of a typical intrinsic (non doped) semiconductor decreases exponentially with temperature R=R0e(α⁄T)
(b) Consider the case when Ge and Si diodes are connected as show in the given figure. Equivalent voltage drop across the combination Ge and Si diode =0.3 V ⇒ Current i=(12-0.3)/(5 kΩ)=2.34 mA