CBSE Class 12 Semiconductor Devices — practice questions
22 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice CBSE Class 12 Semiconductor Devices in the app →Before 1948, electronic devices were mostly vacuum tubes. What was discovered that year?In a vacuum tube electrons flow only from cathode to anode, so such tubes are called:Compared with valves, semiconductor devices are:A material whose resistivity lies between a metal and an insulator is a:In a silicon crystal each atom is surrounded by how many nearest neighbours?Neighbouring Si atoms share electron pairs. Each shared pair forms a:When a bond breaks and an electron leaves, the vacancy left behind behaves like a free particle with:What is special about semiconductors compared with metals regarding carriers?At room temperature, the conductivity of a pure intrinsic semiconductor is:Adding a few parts per million of impurity to a semiconductor makes its conductivity:Deliberately adding an impurity to a semiconductor is called:Arsenic, antimony and phosphorus have valency 5, so they are:A pentavalent dopant gives one extra electron for conduction, so it is called a:Doping silicon with boron, which has three valence electrons, gives:Despite extra carriers, a doped crystal as a whole is:A p-n junction with metal contacts at its ends is a:Under forward bias the depletion layer:A full-wave rectifier built with two diodes needs a transformer with a:Photodiodes, LEDs and solar cells are together called:An LED converts electrical energy into:The five common logic gates are NOT, AND, OR, NAND and:The function of a logic gate is defined by its: