Test Preparation on UGC NET Electronic Science Mock Test-4
1.
Assertion (A) : In amplifiers, it iseasy to compare two powers ona Logarithmic rather than onlinear scale. It is called decibel.Reason (R) : Decibel is defined asN= 10 logP2P1, where P2is outputpower and P1is input power.
2.
Assertion (A) : Magnetron are notcross field devices.Reason (R) : They make use ofelectric and magnetic fieldssimultaneously. The fields areperpendicular to each other.
3.
Assertion (A) : TDM can beemployed to transmit channelshaving unequal bandwidths.Reason (R) : If sampling theorem isstrictly followed, any analogsignal can be reconstructedback from the samples.
4.
Assertion (A) : A NAND gate iscalled a Universal logic element.Reason (R) : Any logic function canbe realized using NAND gatesalone.
5.
Assertion (A) : The stability of acontrol system can bedetermined from the location ofroots of characteristic equation.Reason (R) : For stability the rootsshould lie on the left half ofs-plane.
6.
Assertion (A) : The intrinsic Fermilevel of a semiconductor doesnot lie exactly at the middle ofthe energy band gap.Reason (R) : The densities of theavailable states in valence andconduction bands of anintrinsic semiconductor areequal.
7.
Assertion (A) : The operatingprinciple of Laser is based onstimulated emission process.Reason (R) : In coherent radiation,the emitted photons have samephase, same polarization andsame direction with theincident photon.
8.
Assertion (A) : A microprocessorinterfaced with inputs, outputsand other peripheral devices isalso called a micro controllersystem and is capable ofcontrolling the process.Reason (R) : The microprocessor isa device which processes theinstructions.
