Physics Questions for Railway & SSC CGL Exam 2018: 31st August


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 current year 2018 brought a pleasant surprise with almost 1,20,000 seats to be filled by the valid candidates. Opportunity is here but you have to welcome it with a provident strategy. 

रेलवे बोर्ड अपने उम्मीदवारों के लिए भव्य और प्रतिष्ठित कार्य पदों की पेशकश करता है. और हर साल ऐसा नहीं होता है कि हमें रेलवे की ओर से अधिसूचना मिलती है. लेकिन वर्तमान वर्ष 2018 आपके लिए बहुत सुखद वर्ष है क्योंकि इसमें लगभग 1,20,000 सीटों को वैध उम्मीदवारों द्वारा भरा जाएगा. आपके पास बहुत अच्छा अवसर है और आपको इसे एक बेहतर रणनीति से प्राप्त करना होगा.


Q1. The sun and the moon appear elliptical near the horizon because of : 
सूरज और चंद्रमा क्षितिज के पास अंडाकार दिखाई देते हैं क्योंकि:
(a) Refraction / अपवर्तन
(b) Optical illusion / दृष्टि संबंधी भ्रम
(c) Interference phenomenon / हस्तक्षेप घटना
(d) Their actual shape / उनका वास्तविक आकार

Show Answer
Ans.(a)
Sol. The Sun and the moon appear elliptical near the horizon because of refraction.

Q2. Photosynthesis using the invisible part of the sunlight is done by some- 
सूरज की रोशनी के अदृश्य भाग का उपयोग करके प्रकाश संश्लेषण किस के द्वारा किया जाता है?
(a) Trees / पेड़
(b) Algae / शैवाल
(c) Bacteria/  जीवाणु
(d) Fungi/ कवक

Show Answer
Ans.(c)
Sol. The bacteria which are found at 400-8000 ft into the deep sea, for example green Sulphur bacteria, uses infrared radiations for photosynthesis to produce energy.

Q3. The energy of wind is- 
हवा की ऊर्जा कैसी होती है?
(a) Only potential / केवल स्थितिज ऊर्जा
(b) Only kinetic / केवल गतिज ऊर्जा
(c) Electrical / विद्युतीय
(d) Potential and kinetic both / स्थितिज और गतिज दोनों

Show Answer
Ans.(b)
Sol. The kinetic energy is the energy in moving objects or mass. The kinetic energy of the wind (wind energy) can be converted into electrical or mechanical energy. 

Q4. Photovoltaic cells are: 
फोटोवोल्टिक सेल क्या हैं?
(a) Solar cells / सोलर सेल्स
(b) Thermal cells  / थर्मल सेल्स
(c) Sulphur cells / सल्फर सेल्स
(d) Molar cells / मोल्लर सेल्स

Show Answer
Ans.(a)
Sol. The conversion of light energy into electrical energy is based on the phenomenon  called photovoltaic effect. Silicon is most widely used semiconductor material for construction photovoltaic cell.



Q5. What is the correct equation for finding the acceleration? 
त्वरण खोजने के लिए सही समीकरण क्या है?
(a) a = (v-u)/t
(b) a = u + vt
(c) a = (v+u)/t
(d) a=(v+u)/2

Show Answer
Ans.(a)
Sol. As we know v = u + at or at = v – u
∴a=(v-u)/t
Where, v = ultimate velocity of the particle
u = initial velocity of the particle
a = Acceleration, t = time 



Q6. A drop of water is spherical in shape. This is due to: 
पानी की एक बूंद गोलाकार होती है। इसका कारण क्या है?
(a) Surface tension / सतही-तनाव
(b) Low temperature / कम तापमान
(c) Air resistance / हवा प्रतिरोध
(d) Viscosity of water / पानी की चिपचिपाहट

Show Answer
Ans.(a)
Sol. The shape of a drop of rain is constrained by the surface tension, which tries to give it the shape for which the surface area is minimum for the given volume. The spherical shape has the minimum surface area. That’s why rain drops acquire spherical shape.


Q7. Velocity of light is maximum in- 
प्रकाश की गति अधिकतम किस में होती है?
(a) Diamond / हीरा
(b) Water /पानी
(c) Vacuum / वैक्यूम
(d) Hydrogen / हाइड्रोजन
Show Answer
Ans.(c)
Sol. The speed of light in vacuum is maximum (c = 3 × 108 ms–1). The speed of light decreases gradually in optically denser mediums like water or glass. It is least in diamond.
Q8. Red light signal is used as a danger signal because- 
रेड लाइट सिग्नल को खतरे के सिग्नल के रूप में प्रयोग किया जाता है क्योंकि-
(a) Red light is scattered least /लाल लाइट सबसे कम फेलती है.
(b) This is comfortable for eyes /यह आँखों के लिए आरामदायक होती है.
(c) It produces least chemical reaction / यह कम रासायनिक प्रतिक्रिया पैदा करती है.
(d) It is least absorbed in air / यह हवा में कम अवशोषित होती है.
Show Answer
Ans.(a)
Sol. The red light signal is used as a danger signal because it has the highest wavelength and scattered least.
Q9. Which one of the following colours is seen in the middle of a Rainbow? 
इंद्रधनुष के बीच में निम्नलिखित में से कौन सा रंग देखा जाता है?
(a) Blue / नीला
(b) Green / हरा
(c) Red / लाल
(d) Yellow / पीला
Show Answer
Ans.(b)
Sol. The correct order of colors of the rainbow is Red, Orange, Yellow, Green, Blue, Indigo and Violet. Thus it is clear that ‘Green’ Color is seen in the middle of Rainbow (VIBGYOR).

Q10. In which direction the rainbow is seen at 12 noon? 
12:00 बजे इंद्रधनुष किस दिशा में देखा जाता है?
(a) In the West / पश्चिम
(b) In the South  / दक्षिण
(c) In the East / पूर्व
(d) It cannot be seen / देखा नहीं जा सकता है 
Show Answer
Ans.(d)
Sol. A rainbow is located opposite to the sun; this explains why rainbow is not seen at 12 noon with the sun overhead.

Q11. Total internal reflection can take place when light travels from: 
जब प्रकाश _______ से यात्रा करता है तो कुल आंतरिक प्रतिबिंब हो सकता है
(a) Diamond to glass / हीरे से ग्लास
(b) Water to glass / पानी से ग्लास
(c) Air to water / हवा से पानी
(d) Air to glass / हवा से ग्लास
Show Answer
Ans.(a)
Sol. Total internal reflection takes place when a ray of light is travelling from denser to thinner medium and angle of incidence is greater than the critical angle, the ray is completely reflected from surface and meet each other as if the surface is a mirror. So according to options, the situation of option (a) is correct where total internal reflection takes place, it is because diamond is denser than glass. 
Q12. Which one of the following phenomenon is used in optical fibres? 
ऑप्टिकल फाइबर में निम्न में से कौन सी घटना का उपयोग किया जाता है?
(a) Interference / इंटरफेरेंस
(b) Refraction / अपवर्तन
(c) Total internal reflection / कुल आंतरिक प्रतिबिंब
(d) Polarisation / ध्रुवीकरण
Show Answer
Ans.(c)
Sol. The optical fibre is a very thin strand of glass or plastic cable for transmitting light from one point to another. They work on he principle of total internal reflection. There is no loss of signal through an optical fibre.
Q13. An endoscope is a- 
एंडोस्कोप क्या है?
(a) Narrow telescope / संकीर्ण दूरबीन
(b) Type of camera / कैमरा का प्रकार
(c) Simple microscope / सरल माइक्रोस्कोप
(d) None of these / इनमें से कोई नहीं
Show Answer
Ans.(d)
Sol. An endoscope is a medical device consisting of a long, thin, flexible (or rigid) tube which has a light source and a video camera. Images of the inside of the patient’s body can be seen on a screen. It is not suitable to categorize endoscope as a type of a camera. 
Q14. A cut diamond shines brilliantly due to- 
एक कट हीरा शानदार ढंग से चमकता है-
(a) Total internal reflection / कुल आंतरिक प्रतिबिंब
(b) Absorption of light / प्रकाश का अवशोषण
(c) Some inherent property / कुछ अंतर्निहित संपत्ति
(d) Its molecular structure / इसकी आणविक संरचना
Show Answer
Ans.(a)
Sol. The refractive index of diamond is very high. Diamond achieves brilliance partially from total internal refraction. It has been cut or designed in such a way that if light enters into it, incident light strikes many of the internal surfaces.  
Q15. Which of the following is used to take 3-dimentional pictures-  
निम्नलिखित में से कौन सा 3-आयामी चित्र लेने के लिए उपयोग किया जाता है?
(a) Photography / फोटोग्राफी
(b) Holography / होलोग्राफ़ी
(c) Radiography / रेडियोग्राफी
(d) None of the above / इनमें से कोई नहीं
(d) Water / पानी
Show Answer
Ans.(b)
Sol. Holography is a technique of producing a three-dimensional image of an object. Holography can work with sound, light or any wavelength. It is also been used for three-dimensional natural films. 

 
                 

×

Download success!

Thanks for downloading the guide. For similar guides, free study material, quizzes, videos and job alerts you can download the Adda247 app from play store.

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

Leave a comment

Your email address will not be published. Required fields are marked *

×
Login
OR

Forgot Password?

×
Sign Up
OR
Forgot Password
Enter the email address associated with your account, and we'll email you an OTP to verify it's you.


Reset Password
Please enter the OTP sent to
/6


×
CHANGE PASSWORD