# RRB JE 2019 Exam: Physics Quiz | 25th January

Railway Board offers opulent and revered job posts to its aspirants. And it is not every year that we get the notification from Railway offering a good number of vacant seats to the multitude aspirants. But the last year 2018 brought a pleasant surprise with almost 1,27,278 seats to be filled by the valid candidates. Opportunity is here but you have to welcome it with a provident strategy.

Q1. Which set of conditions represents the easiest way to liquefy a gas ?
स्थितियों का कौन सा सेट एक गैस को द्रवीभूत करने का सबसे आसान तरीका दर्शाता है?
(a) Low temperature and high pressure/ कम तापमान और उच्च दबाव
(b) High temperature and low pressure/ उच्च तापमान और कम दबाव
(c) Low temperature and low pressure/ कम तापमान और कम दबाव
(d) High temperature and high pressure/ उच्च तापमान और उच्च दबाव

S1.Ans(a)
Sol. Low temperature and high pressure set of conditions represents the easiest way to liquefy a gas. Liquefaction of gases is physical conversion of a gas into a liquid state (condensation). The processes are used for scientific, industrial and commercial purposes. Many gases can be put into a liquid state
at normal atmospheric pressure by simple cooling.

Q2. What is colour of light related to ?
प्रकाश का रंग किससे संबंधित होता है?
(a) wavelength/ तरंग दैर्ध्य
(b) Frequency/ आवृत्ति
(c) Quality/ गुणवत्ता
(d) Velocity/ वेग

S2.Ans (a)
Sol. The colour of visible light depends on its wavelength. These wavelengths range from 700 nm at the red end of the spectrum to 400 nm at the violet end. White light is actually made of all of the colours of the rainbow because it contains all wavelengths, and it is described as polychromatic light.

Q3. What principle/law explains the working of the hydraulic brakes in automobiles ?
ऑटोमोबाइल में हाइड्रोलिक ब्रेक के कार्य को कौन से सिद्धांत / कानून स्पष्ट करते हैं?
(a) Bernoulli’s law/ बर्नौली का नियम
(b) Posieulle’s principle/ पोजीउल का सिद्धांत
(c) Pascal’s law/ पास्कल का नियम
(d) Archimedes’ principle/ आर्किमिडीज का सिद्धांत

S3.Ans (c)
Sol. Hydraulic brakes work on the principle of Pascal’s law which states that “pressure at a point in a fluid is equal in all directions in space”. According to this law when pressure is applied on a fluid it travels equally in all directions so that uniform braking action is applied on all four wheels.

Q4. The best conductor of heat among the following is
निम्नलिखित में से ऊष्मा का सबसे अच्छा सुचालक है-
(a) alcohol / अल्कोहॉल
(b) mercury/पारा
(c) ether / ईथर
(d) water/पानी

S4.Ans (b)
Sol. Since mercury is 13+ times as dense as water, a given volume of mercury would carry about 4.4 times as much heat, so mercury is best conductor of heat among the given options. It is the only metal that is liquid at standard conditions for temperature and pressure.

Q5. What is viewed through an electron microscope?
एक इलेक्ट्रॉन माइक्रोस्कोप के माध्यम से क्या देखा जाता है?
(a) Electrons and other elementary particles/ इलेक्ट्रॉन और अन्य प्राथमिक कण
(b) Structure of bacteria and viruses / बैक्टीरिया और वायरस की संरचना
(c) Inside of human stomach/ मानव पेट के अंदर
(d) Inside of the human eye/ मानव आँख के अंदर

S5.Ans (b)
Sol. Electron microscopes are used to observe a wide range of biological and inorganic specimens including microorganisms, cells, large molecules, biopsy samples, metals, and crystals. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.

Q6. What apparatus is used to locate a submerged object?
जलमग्न वस्तु का पता लगाने के लिए किस उपकरण का उपयोग किया जाता है?
(b) Sonar/
(c) Quasar/ क्वेसार
(d) Pulsar/ पलसर

S6.Ans (b)
Sol. Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name “sonar”: passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of “targets” in the water.

Q7. The instrument which uses sound waves to measure the depth of oceans is
वह उपकरण जो महासागरों की गहराई को मापने के लिए ध्वनि तरंगों का उपयोग करता है?
(b) Sonar/ सोनार
(c) Altimeter/ तुंगतामापी
(d) Venturimeter/वेंतुरीमीटर

S7.Ans (b)
Sol. The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of “targets” in the water.

Q8. Which combination of colour is the most convenient during day and night time ?
रंग का कौन सा संयोजन दिन और रात के समय में सबसे सुविधाजनक है?
(a) Organe and blue/ नारंगी और नीला
(b) White and black/सफ़ेद और काला
(c) Yellow and blue/पीला और नीला
(d) Red and green/लाल और हरा

S8.Ans(d)
Sol.Red and green is the most convenient combination during day and night time because of very precise visibility. In modern colour theory, also known as the RGB colour model, red, green and blue are additive primary colours. Red, green and blue light combined together makes white light, and these three colours, combined in different mixtures, can produce almost any colour.

Q9. The instrument that measures and records the relative humidity of air is
वह उपकरण जो हवा की सापेक्ष आर्द्रता को मापता और रिकॉर्ड करता है?
(a) Hydrometer/ हाइड्रोमीटर
(b) Hygrometer/ हाइग्रोमीटर
(c) Lactometer / लाकटोमीटर
(d) Barometer/ बैरोमीटर

S9.Ans (b)
Sol. A hygrometer is an instrument used for measuring the moisture content in the environment. Humidity measurement instruments usual ly rely on measurements of some other quantity such as temperature, pressure, mass or a mechanical or electrical change in a substance as moisture is absorbed. By calibration and calculation, these measured quantities can lead to a measurement of humidity. Modern electronic devices use temperature of condensation, or changes in electrical capacitance or resistance to measure humidity changes. Besides greenhouses and industrial spaces, hygrometers are also used in some incubators (egg), saunas, humidors and museums.

Q10. The shape of our milky way galaxy is
हमारी आकाशगंगा का आकार क्या है?
(a) circular/ गोलाकार
(b) elliptical/ दीर्घ वृत्ताकार
(c) spiral/ स्पाइरल
(d) None of these/इनमें से कोई नहीं

S10.Ans(c)
Sol. The Milky Way is a barred spiral galaxy 100,000– 120,000 light-years in diameter containing 200–400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars.

×

Thank You, Your details have been submitted we will get back to you.

×
OR

×