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#QuestionSubject and topicDifficulty
181 Nuclear fusion needs extremely high temperatures mainly because: Physics
Nuclear fission and fusion		 Medium
182 Each fission of U-235 releases about 200 MeV. Roughly how much energy is released if all the nuclei in 1 kg o… Physics
Nuclear fission and fusion		 Hard
183 In which type of solid do the valence and conduction bands overlap? Physics
Energy bands		 Easy
184 Diamond is a good electrical insulator mainly because: Physics
Energy bands		 Easy
185 A pure silicon crystal is cooled to 0 K. How does it behave? Physics
Energy bands		 Medium
186 As the temperature of a pure semiconductor increases, its resistance: Physics
Energy bands		 Medium
187 Silicon has a band gap of 1.1 eV. What is the longest wavelength of light that can excite an electron from it… Physics
Energy bands		 Hard
188 To make n-type silicon, the impurity added should be: Physics
Semiconductors		 Easy
189 In a p-type semiconductor, the majority charge carriers are: Physics
Semiconductors		 Easy
190 An n-type semiconductor has many more free electrons than holes. What is the net charge on the crystal? Physics
Semiconductors		 Medium
191 In the energy band diagram of a p-type semiconductor, the acceptor energy level lies: Physics
Semiconductors		 Medium
192 Silicon with nᵢ = 1.5 × 10¹⁶ m⁻³ is doped so that the electron concentration is 5 × 10²² m⁻³. What is the hol… Physics
Semiconductors		 Hard
193 When a p-n junction is forward biased, the width of the depletion region: Physics
p-n junction diode		 Easy
194 The small current through a reverse-biased p-n junction is mainly due to: Physics
p-n junction diode		 Medium
195 A full-wave rectifier is fed from 50 Hz AC mains. What is the fundamental frequency of the ripple in its outp… Physics
p-n junction diode		 Medium
196 In the forward-bias region of a diode, increasing the voltage by 0.1 V increases the current by 20 mA. What i… Physics
p-n junction diode		 Easy
197 A silicon diode with a forward voltage drop of 0.7 V is connected in forward bias in series with a 1 kΩ resis… Physics
p-n junction diode		 Hard