InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 2001. |
Ultrasonics are used in SONAR with greatest advantage because ultrasonics: |
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Answer» have LOW frequency |
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| 2002. |
What is the basic cause of an induced emf ? |
| Answer» Solution :The basic cause of an induced EMF is the change of MAGNETIC FLUX LINKED with a closed CIRCUIT. | |
| 2003. |
Whatchanges canyou make in your habits to become more enviroment friendly ? |
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Answer» Solution :We can make the following changes in our habits to become more enviroment friendly , (i)we must collect plastic , paper , glass and metail items and recycle and reusethem to make the required things instead of synthesising fresh plastic , paper , glass or METALS. (ii)By closing the TAPS when water is not needed. (III) By planthing trees. (iv)Save the energy by SWITCHING off unnecessary lights and fans. (v)Reducing the use of non - RENEWABLE energy sources like petrol , diesel , etc. |
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| 2004. |
How can specific heat capacity of monoatomic, diatomic and polyatomic gases be explained on the basis of Law of equipartition of Energy? |
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Answer» Solution :From LAW of equipartition of energy, energy per each degree of freedom is `1/2 k_(B)T` per atom or molecule. 1. Monoatomic GAS has three degrees of freedom. `:. U_(1) = 3xx1/2K_(B).T or (dU)/(dT) = 3/2K_(B).T` But molar specific heat at constant volume `C_(V) = (dU)/(dT)` `:. C_(V) = 3/2 K_(B)TN_(A) , But K_(B)N_(A)=R` `:. C_(V) = 3/2RT, But C_(P) = C_(V) +R :. C_(P) = 5/2 R` (2) A diatomic gas has 3 TRANSLATIONAL and two rational degrees of freedom `:.` Kinetic energy per molecule `U_(1) = 5.1/2 K_(B).T` For one gram MOLE total energy `U = 5/2K_(B).T.N_(A)` Molar specific heat at constant volume `C_(V) = (dU)/(dT) =5/2 K_(B) . N_(A)` `:. C_(V) = 5/2 R & C_(P) = 5/2 R + R= 7/2 R` (3) A polyatomic gas has three translational three ratitional and at least one vibrational degrees of freedom. `:.` Kinetic energy per molecule `U_(1) = 3.1/2K_(B) . T + 3 .1/2 + f = (3+f)K_(B)T` f = Number of vibrational degree of freedom kinetic energy = per gram mole of MOLECULES `= U_(1)N_(A) = U = (3+f)K_(B) . N_(A) . T = (3+f)RT` Molar specific heat `C_(V) = (dU)/(dT) = (3+f)R` `:. C_(P) = (u+f)R` `:.` For polyatomic gases `C_(V) = (3+f)R & C_(P) = (4+f)R`. |
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| 2005. |
Bharat was doing an experiment by using an ammeter. Suddenly. it fell from his hand and broke. He was afraid. that he might be scolded and threaten by his teacher. His classmate advised him not to tell the teacher. but he refused and told his teacher. On listening lu him patiently, the teacher did not scold him and threaten as it was just an accident and used the opportunity to show the internal structure of the ammeter to the whole class. On the basis of above passage, answer thefollowing questions: What is the use of ammeter? How is it connected in the circuit? |
| Answer» Solution :An ammeter is used to MEASURE the electric current FLOWING in a circuit. It is ALWAYS connected in SERIES in a circuit. | |
| 2006. |
How is solar energy used in solar therrnal power plants?: Give one advantages and one disadvantage of this energy. |
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Answer» SOLUTION :Advantage of solar energy : Solar energy is eco-friendly which does not create POLLUTION. It is boundless SOURCE. Disadvantage of solar energy : Soalr energy is avilable only when sun is in the sky. THEREFORE, it has to be stored in batteries. |
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| 2007. |
Bharat was doing an experiment by using an ammeter. Suddenly. it fell from his hand and broke. He was afraid. that he might be scolded and threaten by his teacher. His classmate advised him not to tell the teacher. but he refused and told his teacher. On listening lu him patiently, the teacher did not scold him and threaten as it was just an accident and used the opportunity to show the internal structure of the ammeter to the whole class. On the basis of above passage, answer thefollowing questions: State the aim of anyone experiment, where Bharat could have used the ammeter. |
| Answer» Solution :BHARAT could have used the AMMETER to verify the Ohm.s LAW. | |
| 2008. |
How did the change in momentum achieved ? |
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Answer» Solution :CHANGE in momentum can be achieved in two ways. They are : (i) A LARGE force acting for a SHORT period of TIME and (ii) A smaller force acting for a longer period of time. |
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| 2009. |
Differentiate irreversible and reversible reactions. |
| Answer» SOLUTION :`{:("Reversible Reaction","IRREVERSIBLE Reaction"),("Reaction can be reversed","Reaction cannot be reversed"),("it PROCEEDS in both DIRECTIONS,"It is unidirectional"),("It attains equilibrium","Equilibrium is not attained"),("It is relatively slow","It is FAST"):}` | |
| 2010. |
Bharat was doing an experiment by using an ammeter. Suddenly. it fell from his hand and broke. He was afraid. that he might be scolded and threaten by his teacher. His classmate advised him not to tell the teacher. but he refused and told his teacher. On listening lu him patiently, the teacher did not scold him and threaten as it was just an accident and used the opportunity to show the internal structure of the ammeter to the whole class. On the basis of above passage, answer thefollowing questions:What values do you learn from Bharat? |
| Answer» SOLUTION :The values LEARNT from Bharat are HONESTY. confidence and courage. | |
| 2011. |
Explain the method of converting ethanol into ethanoic acid with the help of chemical equation. |
Answer» SOLUTION :Oxidation of ethanol using acidified potassium DICHROMATE GIVES ethanal in first step which on further oxidation by same OXIDISING AGENTS gives ethanoic acid.
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| 2012. |
Nichrome is. . . . . . . . . . .. |
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Answer» a CONDUCTOR |
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| 2013. |
Street icecreamvendorsremovethe waterin theirfreezingmixtureinteremittently, asaresultofwhich______. |
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Answer» THETEMPERATUREOF thefreezingmixtureincreases |
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| 2015. |
A copper coil is connected to a galvanometer. What would happen if a bar magnet is (i) pushed into the coil with its north pole entering first (ii) held at rest inside the coil (iii) pulled out again? |
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Answer» SOLUTION :(i) When north pole is PUSHED into the coil, a MOMENTARY deflection is observed in the GALVANOMETER. This deflection indicates that a momentary current is produced in the coil. The direction of current in the coil is anticlockwise. (ii) When the magnet is held at rest, there is no deflection in the galvanometer. It indicates that no current is produced in the coil in this use. (iii) In PULLING the magnet out of the coil, a deflection in opposite direction is observed. It indicates that the current produced in the coil is in opposite direction. |
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| 2016. |
The equivalent resistance in a _________ combination is less than the lowest of the individual resistances. |
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Answer» |
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| 2017. |
The following apparatus is available in a laboratory. Cell : Adjustable from 0 to 4.5 volt Resistors : 3Omega and 6Omega Ammeters : A_(1) of Range 0 to 3 A, Least count 0.1 A A_(2) of Range 0 to 1 A, Least count 0.05 A Voltmeters : V_(1) of Range 0 to 10 V, Least count 0.5 V V_(2) of Range 0 to 5V, Least count 0.1 V Find the best combination of voltmeter and ammeter for finding the equivalent resistance of the resistors in series. |
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Answer» Solution :Equivalent resistance, R `=3Omega+6Omega=9Omega MAXIMUM VOLTAGE to be measured `=4.5 V` Maximum current to be measured `=(V)/(R)=(4.5)/(9)=0.5A` These requirements of measuring this current and voltage are fulfilled by AMMETER `A_(2)` and voltmeter `V_(2)`. Also these two instruments are more accurate due to their samller least counts `0.05` A and `0.1` V respectively. |
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| 2018. |
(a) Explain feed back mechanism for regulationof hormonal secretion with the help of one example . (b) State two different types of movement in plant. Mention two points of difference between them. |
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Answer» Solution :(a) The timing and amount of hormones relaased by various glands are controlled by the 'feedback mechanism' which isin-bulit in our body. Example, if the SUGER level in the blood rises too much, it is detected by the CELLS of pancreas which responds by producing and secreting more INSULIN into the blood, and as the blood suger fallsto a cartain level the secretion of insulin in reduced automatically. (b) The plant movements made in response to external stimuli fall into two main categories - (i) tropism and (II) nasties . Tropisms. A growth movementsmade in repsonse to external stimuli in which the dircetion of stimulus determines the direction of response is called tropism . So itis a directional movement. Nasties. The movement of a plant part in response to an external stimuli in the direction of response is not determined by the direction of stimulus is called nastic movement.  .
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| 2019. |
Material: A tray with thick layer of wax, solid spheres of iron, lead and copper of equal mass, burner or spirit lamp, large beaker. Procedure: i. Take three spheres of iron, copper and lead of equal mass. |
| Answer» SOLUTION :DEPTH of each sphere in wax SLAB is different. | |
| 2020. |
Calculate the heat in joules, generated in a coil of resistance 400 'omega' in 2 minutes when a potential difference of 200 V is applied to it. |
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Answer» |
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| 2021. |
Material: A tray with thick layer of wax, solid spheres of iron, lead and copper of equal mass, burner or spirit lamp, large beaker. Procedure: ii. Put all the three spheres in both water m the beaker for same time. |
| Answer» SOLUTION :It is maximum for IRON, intermediate for copper and minimum for LEAD SPHERE. | |
| 2022. |
Is it possible that no transfer of energy take place even a force is applied to a body ? |
| Answer» SOLUTION :YES ,When FORCE is NORMAL to DISPLACEMENT | |
| 2023. |
What is the minimum wind velocity required to obtain useful energy with a windmill? |
| Answer» SOLUTION :15 km/hour or more. | |
| 2024. |
Name the device used to convert (a) solar energy into heat, and (b) solar energy into electricity . (ii) Explain the principle of working of a windmill. |
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Answer» Solution :(i) (a) Solar energy into heat: Solar cooker. (b) Solar energy into ELECTRICITY : Solar cell. (ii) The wind rotates the blades of the WINDMILL. This, in TURN rotates the connecting rod (shaft) and the crank (u-bend) MOVES up and down . Since the pump rod is connected to the crank, the pump rod of the water pump also moves up and down and lifts the water from the well or flooded mine. Thus, the rotational movement of the blades of the windmill is used to drive a large number of machines. |
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| 2025. |
The decreased heart beat is called.................... |
| Answer» Answer :A | |
| 2026. |
How would its motion have been if no such force acted on it ? |
| Answer» Solution :If there was no force ACTING on the moon, it would have moved along a straight LINE which is the tangent to the CIRCLE | |
| 2027. |
Environmental Management : |
Answer» SOLUTION :
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| 2029. |
A satellite revolves around a planet in a circular orbit. What is the work done by the satellite at any instant ? Give a reason. |
| Answer» Solution :reason:FORCE of gravity on the satellite is normal to its DISPLACEMENT. | |
| 2030. |
Give the advantages of using AC in daily life . |
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Answer» Solution :ADVANTAGES of usingACin dailylife AREAS follows . (1) Relative to theproduction of DC, it iseasier and economicaltoproduce ACC. (2) AC power can betransmitted over longer distancewithoutmuch lossof electricty (electric energy). [A device ,CALLED a TRANSFORMER, is usedto increase or decrease AC voltage ]. |
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| 2031. |
Hydro power plants convert the ………. energy of falling water into electricity. |
| Answer» SOLUTION :POTENTIAL. | |
| 2032. |
Children are facing the problems of loneliness and mental stress due to reasons like ……….and parents staying outdoors due to job. |
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Answer» |
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| 2033. |
Draw a circuit as mentioned below i. Total number of resistance are 4. They are 5Omega,2Omega,4Omegaand6Omega ii. 5Omegaand6Omegaare in parallel iii. 4Omegaand6Omega are in parallel iv. 5Omegaand2Omega are in series v. 2Omegaand4Omega are in series |
Answer» SOLUTION :
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| 2034. |
Thetemperatureof icecanbedercreasedbelow 0^(@)Cbymixing______ init . |
| Answer» Answer :C | |
| 2035. |
.................. is a relative periodic property. |
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Answer» ATOMIC radii |
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| 2036. |
Your friends has devolped the hobby of snapping selfies . |
| Answer» Solution :The HOBIT of continuously TAKING selfie is bad.It shows that the friends is constantly thinkings of himself only, His self-centredness is to e removed by COUNSELLING him.The reason behind this behaviour should also be undrstood. He should be diverted and motivated to TAKE some other tasks so that his habit can be lessened. Taking selfies is not a hobby.It is a bad habit if SOMEONE is repeatedly engaged in it. | |
| 2037. |
Which of the following is a man-madedisaster? |
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Answer» Earthquake |
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| 2038. |
The axis of a fixed edge about which the dooris rotatedis called _________. |
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Answer» AXIS of ROTATION |
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| 2039. |
No real engine can have an efficiency greater than that of a carnot engine working between the same two temperatures, why? |
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Answer» Solution :In carnot engine. (i) There is absolutely no friction between the wall of cylinder and piston. (ii) WORKING SUBSTANCE is an ideal gas In real engine these condition cannot be fulfilled. |
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| 2040. |
When ever magnetic field of a coil changes, a voltage is induced across the ends of the coil. |
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Answer» |
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| 2041. |
Radius of curvature of a mirror is 20 cm, it is a : |
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Answer» CONVEX mirror |
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| 2042. |
The near point of a person suffering from hypermetropia is 75 cm. Calculate the focal length and power of the lens required to enable him to read the newspaper which is kept at 25 cm from the eye. |
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Answer» Solution :`u=-25cm` `v=-75 cm` `(1)/(v)-(1)/(u)=(1)/(F)` `(1)/(-75)-(1)/(-25)=(1)/(f)rArr (1)/(-75)+(1)/(25)=(1)/(f)` `(2)/(75)=(1)/(f)` `rArr""f=(75)/(2)=37.5cm` `"So,P"=(100)/(37.5)` `=2.6D` |
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| 2043. |
Power of a lens is a measure of the ability of the lens to converge the rays of light falling on it. Quantitatively, power of a lens = reciprocal of focal length of lens, i.e., P=(1)/(f). If a lens happens to diverge the ray of light falling on it, its power is said to be negative. Thus, power of a convex lens is positive and power of a concave lens is negative. If P_1,P_2 are powers of two lenses held in contact with eachother, the power of the combination is P=P_1+P_2. Note that P_1,P_2 are to be added with proper sign. Read the above passage and answer the following question: (i) What is the SI unit of power? (ii) Focal length ofa concave lens is 20 cm. What is its power ? (iii) What lessons of life do you learn from the relation P=P_1+P_2? |
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Answer» Solution :(i) SI unit of power is diopter (D). One diopter is the power of lens of focal length one meter. (ii) Here, `F =- 20 cm = -20/100 m= -1/5m.P=(1)/(f)=(1)/(-1//5) = -5D` (iii) If `P_1=3D` and `P_2 = - 2D` then `P=P_1+P_2=3D-2D=1 D` Again, if `P_1=3 D` and `P_2 = 2 D`, then `P = P_1 + P_2 = 3D +2D = 5D` i.e., power of combination is much larger when the two lenses are of same NATURE. The same is true in real LIFE. To MAKE a powerful combination in business, partners should PREFERABLY be of same nature. Same is true for life partners, i.e., husband and wife. If their nature is identical, they will make an adorable couple. |
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| 2044. |
Equal masses of oxygen and helium gases are supplied equal amount of heat. Which gas will undergo a greater temperature rise and why? |
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Answer» Solution :Heat SUPPLIED to oxygen `=` Heat supplied to Helium `mc_(1)DeltaT_(1)=mc_(2)DeltaT_(2)` `(DeltaT_(1))/(DeltaT_(2))=(c_(2))/(c_(1))`, As `CXX(1)/(m)`, `m=` molecular mass `(DeltaT_(1))/(DeltaT_(2))=(c_(2))/(c_(1))=(m_(1))/(m_(2))`, As `m_(1) gt m_(2)` `DeltaT_(1) gt DeltaT_(2)` |
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| 2045. |
What is a good source of energy ? |
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Answer» SOLUTION :A good SOURCE of energy is which : (i) Is EASILY ACCESSIBLE. (ii) Is economical (III) Is easy to store and transport |
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| 2046. |
Human eye can be compared to |
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Answer» binoculars |
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| 2047. |
Draw a closed circuit diagram consisting of 0.5 m long nichrome wire XY, an ammeter, a voltmeter, four cells of 1.5 V and a plug key. |
Answer» SOLUTION :
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| 2048. |
The refractive index of four substance A,B, C and D are 1.31, 1.43 , 1.33 , 2.4 respectively . The speed of light is maximum in |
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Answer» A |
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| 2049. |
Three students measured the focal length of a convex lens using parallel rays from distant object. All of the measured the distance between the lens and the inverted image on the screen. Student A saw a sharp image on the screen and labelled the distance as f_(1). Student B saw a slightly larger blurred image on the screen and labelled the distance as f_(2). Student C saw a slightly smaller blurred image on the screen and labelled the distance as f_(3) . What is the relation between the three measurements? |
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Answer» Solution :A sharp image is FORMED at FOCUS. A slightly blurred LARGER image is formed beyond the focus and a slightly blurred SMALLER image is formed before the focus. THEREFORE, `f_(3)ltf_(1)ltf_(2))`. |
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| 2050. |
Explain two disadvantages of series arrangement for household circuit. |
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Answer» Solution :(i) Current is constant in SERIES combination, so it is impractical to connect a bulb and an electric heater in series. (ii) When one component fails, the CIRCUIT is broken and none of the components WORK. |
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