29/03/2020 Direct Sensing(Senior Class Physics Study by Topics) 0Comments by Gate Academy Welcome to your Direct Sensing(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. What type of component has a change in resistance with temperature?VaristorPhotoconductive cellThermistorWire wound resistors2. Which of the following best describes the behaviour of a Thermistor.Its resistance increases if the voltage increasesIts resistance decreases if the voltage increasesIts resistance decreases if the temperature increasesIts resistance decreases if the current increases3. A piezoelectric transducer has a _________high sensitivityzero sensitivitylow sensitivityvery low sensitivity4. _________ is the most common measurement scale for a manometer. Vacuum manometerPressure gauge manometerBourbon tube manometerU-tube manometer5. What does temperature coefficient mean? How much the resistance, voltage or current of a device changes with heat or cold. For a thermistor it is the amount of resistance changeHow hot the device can get before damage occurs.Change in temperatureThe temperature at which the device has zero ohms.6. Pressure measuring device with two fluid chamber tube gauges connected by a U-shaped tube Differential pressure cellManometerCapacitance transducerStrain gauge transducer7. What colour does living vegetation appears as on false-colour IR images? BlackBlueRedGreen8. In kitchen applications a piezoelectric crystal is used for _________grindinglighting a gas stoveskimming milkmixing9. What type of component changes its resistance with changes in voltage? As voltage increases the resistance decreases. Wire wound resistorsPhotoconductive cellVaristorThermistor10. Piezoelectric crystals __________are not soluble in waterabsorb waterdissolve in waterfloat on water11. What is photogrammetry?Estimating the three-dimensional coordinates of points on an objectOptical illusion of depth created from flat, two-dimensional image or imagesAnalysing a real-world object or environment to collect data on its shape and possibly its appearanceDetermining the geometric properties of objects from photographic images12. Generally speaking, transmitters are ___________.Differential pressure transmittersThermocouplesTransducersOut dated13. A Thermistor is a thermal resistor. TrueFalse14. Which of the following is the most common type of Thermistor? VaristorPTC thermistorNTC thermistorMOV15. The photoconductive cell has an increase in conduction when exposed to photon energy (light) which releases free electrons. The extra free electrons lowers the resistance of the cell allowing more current flow.FalseTrue16. What range of colours are used is for the sensing, representation, and display of images in modern electronic systems and photography. Cyan, Magneta, YellowRed, Green, BlueCyan, Green, YellowCyan, Magneta, Yellow, Black17. The following are true about temperature coefficient exceptMOVs should have a high temperature coefficient.Resistors should have zero temperature coefficient.Thermistor can have either a positive or negative temperature coefficient determined by the method and type of material used.Photoconductive cells should have zero temperature coefficient.18. A quartz crystal is _________not a self-generating transducera self-generating transducera chemical transducera photoelectric transducer19. What materials are reed relays made of ?None of the aboveInsulatorsNon ferrous metalsFerrous metals20. Piezoelectric crystals produce _________no voltagelow voltagevery high voltagehigh voltage21. Electromagnetic waves are defined to behave in the same way of which of the following waves? Compressional wavesMechanical waveTransverse wavesLongitudinal waves22. A resolution merge can greatly enhance an image because it can increase the resolution of a low-resolution imageit can use the real color of a low-resolution image to enhance a monochromatic high-resolution image.it can change a satellite image into a aerial photograph.it allows you to hand color an image using Drawing tools.23. _________ is the atmospheric pressure at sea level Normal PressureAbsolute pressureAll of the aboveStandard atmospheric pressure24. Which of the types of waves below has the longest wavelength?Radio WavesGamma RaysHertzian WavesX-Rays25. Which of the following devices has high resistance in total darkness? VaristorWire wound resistorsThermistorPhotoconductive cell26 out of 25Time is Up!