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This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
find out the incorrect order of bond angles 1-NO2+ > NO2 >NO2-2-CH4 > NH3 >H2O3- H2O > H2S > H2Se4-NH3 |
| Answer» correct explanation to this ans is option (4). since the orbitals of the successive elements in group 15 elements increases so the repulsion bw the orbitals also increases leading to decrease in bon angles of the successive elements so the correct order of bond angles of g- 15 is NH3>PH3>..... | |
| 2. |
Increase in temperature of a gas filled in a container would lead to : (1) Increase in its mass (2) Increase in its kinetic energy (3) Decrease in its pressure (4) Decrease in intermolecular distance |
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Answer» The correct option is (2) Increase in its kinetic energy. Explanation: Increase in temperature would lead to the increase in kinetic energy of gas (assuming far as to be ideal) as U = F/2 nRT |
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| 3. |
Write a letter in 100-120 words , to the editor of national daily ,I lighting the hazards of irregular power break down and offering some solution. You are Arun/Arunima use the hints given below;Frequent power cut- 10 hours-no notification-distrupt activity- Sleep effected-road accidents or alternative ways to generate electricity. |
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Answer» Self Address Date Address of the editor e.g. The editor The statesman Kolkata Sir, Frequent power cuts in our area have become a very big problem in our day to day life. There is hardly any area which is not affected by this problem. The whole society and system are paralysed for the time being. We are suffering from this problem from several days. We are not getting proper electric current for our work. It has become a headache thereby obstructing our daily life routine. We are not able to use our gadgets because of this load shedding and thus we have become digitally blind. In this hot and humid summer we are frequently falling ill and also not getting a proper sleep. Students are the worst sufferers of this problem. Our annual examination is knocking at the door we are not able to study properly and also we are unable to prepare fully for coming examination. I therefore request you to highlight this load shedding issue of our area so that the attention of the authorities of our service station can be drawn up on this problem. I will be highly obliged. |
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| 4. |
Which of the following is the most important cause for animals and plants being driven to extinction? (1) Habitat loss and fragmentation (2) Drought and floods (3) Economic exploitation (4) Alien species invasion |
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Answer» Correct option: (1) Habitat loss and fragmentation Explanation: Habitat loss and fragmentation is the most important cause driving animals and plants to extinction. eg: Loss of tropical rainforest reducing the forest cover from 14 % to 6 %. |
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| 5. |
Evaluate:\(\int\limits_{-2}^2\frac{1}{1+e^x}dx\) |
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Answer» Let I = \(\int\limits_{-2}^2\frac{1}{1+e^x}dx\)----(1) \(\therefore\) I = \(\int\limits_{-2}^2\frac{1}{1+e^{-x}}dx\) ⇒ I = \(\int\limits_{-2}^2\frac{e^x}{1+e^x}dx\)----(2) \(\therefore\) 2I = \(\int\limits_{-2}^2\frac{1+e^x}{1+e^x}dx\) (By adding (1) and (2)) ⇒ I = \(\frac12\int\limits_{-2}^{2}dx = \frac12x^2_{-2}\) = \(\frac12(2-(-2))=\frac12\times4=2\) |
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| 6. |
A parallel plate capacitor of capacitance 20 μF is being charged by a voltage source whose potential is changing at the rate of 3 V/s. The conduction current through the connecting wires, and the displacement current through the plates of the capacitor, would be, respectively. (1) Zero, 60 μA (2) 60 μA, 60 μA (3) 60 μA, zero(4) Zero, zero |
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Answer» Answer given below: https://bit.ly/303h7p4 |
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| 7. |
Enzymes that utilize ATP in phosphate transfer require an alkaline earth metal (M) as the cofactor. M is :(1) Be(2) Mg(3) Ca(4) Sr |
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Answer» Correct option (2) Mg Explanation: All enzymes that utilize ATP in phosphate transfer require magnesium(Mg) as the co-factor. |
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| 8. |
Which ion would you expect to have the maximum splitting of d-orbitals |
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Answer» The correct answer is is (b) because [Fe(CN)6]−3 = Fe3+, d5 low spin C.FS.E = -2.0 Δo + 2P |
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| 9. |
Kirchhoff's first rule ΣI = 0 and second rule ΣIR = ΣE (where the symbols have their usual meanings) are respectively based on - (a) conservation of momentum and conservation of charge (b) conservation of energy, conservation of charge (c) conservation of charge, conservation of momentum (d) conservation of charge, conservation of energy |
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Answer» Option : (d) conservation of charge, conservation of energy |
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| 10. |
Consider the following statement : (A) Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group. (B) A complete catalytic active enzyme with its bound prosthetic group is called apoenzyme. Select the correct option. (1) Both (A) and (B) are true. (2) (A) is true but (B) is false. (3) Both (A) and (B) are false. (4) (A) is false but (B) is true. |
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Answer» Correct option: (2) (A) is true but (B) is false. Explanation: Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group. A complete catalytic active enzyme with its bound prosthetic group is called holoenzyme. Actually , Coenzymes and metal Ions that are bound very tightly to the enzyme protien are called prosthetic groups ! This is absolute correct statement . This is because coenzymes are of two types - cosubstrates which are loosely bound and prosthetic grup which are tightly bound . A complete catalytic active enzyme with its bound prosthetic group is called holoenzyme . So A is true and B is false |
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| 11. |
please provide answer with appropriate explanation |
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Answer» The correct option is (d) It have more resonance and alpha hydrogen bond. |
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| 12. |
State Kirchhoff’s loop rule. |
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Answer» Kirchhoff’s loop rule states that the sum of all the electric potential differences around a loop is zero. It is also sometimes called Kirchhoff’s voltage law or Kirchhoff’s second law. This means that the energy supplied by the battery is used up by all the other components in a loop, since energy can’t enter or leave a closed circuit. The rule is an application of the conservation of energy in terms of electric potential difference, Delta ΔV. Mathematically, this can be written as: =ΣΔV=0 |
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| 13. |
Which of the following statements is incorrect? (1) Viroids lack a protein coat. (2) Viruses are obligate parasites. (3) Infective constituent in viruses is the protein coat. (4) Prions consist of abnormally folded proteins. |
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Answer» Correct option: (3) Infective constituent in viruses is the protein coat. Explanation: Infective constituent in viruses is either DNA or RNA, not protein. |
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| 14. |
Which of the following statements regarding mitochondria is incorrect? (1) Outer membrane is permeable to monomers of carbohydrates, fats and proteins. (2) Enzymes of electron transport are embedded in outer membrane. (3) Inner membrane is convoluted with infoldings. (4) Mitochondrial matrix contains single circular DNA molecule and ribosomes. |
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Answer» Correct option: (2) Enzymes of electron transport are embedded in outer membrane. Explanation: In mitochondria, enzymes for electron transport are present in the inner membrane. |
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| 15. |
Which is of the following statements is incorrect? (1) Morels and truffles are edible delicacies. (2) Claviceps is a source of many alkaloids and LSD. (3) Conidia are produced exogenously and ascospores endogenously. (4) Yeasts have filamentous bodies with long thread-like hyphae. |
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Answer» Correct option: (4) Yeasts have filamentous bodies with long thread-like hyphae. Explanation: Yeast is an unicellular sac fungus. It lacks filamentous structure or hyphae. |
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| 16. |
Following statements describe the characteristics of the enzyme Restriction Endonuclease. Identify the incorrect statement. (1) The enzyme cuts DNA molecule at identified position within the DNA. (2) The enzyme binds DNA at specific sites and cuts only one of the two strands. (3) The enzyme cuts the sugar-phosphate backbone at specific sites on each strand. (4) The enzyme recognizes a specific palindromic nucleotide sequence in the DNA. |
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Answer» Correct option: (2) The enzyme binds DNA at specific sites and cuts only one of the two strands. Explanation: Restriction enzymes cut DNA molecules at a particular point by recognising a specific sequence. Each restriction endonuclease functions by inspecting the length of a DNA sequence. Once it finds its specific recognition sequence, it will bind to the DNA and cut each of the two strands of the double helix at specific points in their sugarphosphate backbone. |
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| 17. |
An engine whistling at a constant frequency `n_(0)` and moving with a constant velocity goes past a stationery observer. As the engine crosses him, the frequency of the sound heard by him changes by a factor f. The actual difference in the frequencies of the sound heard by him before and after the engine crosses him isA. `(1)/(2)n_(0)(1-f^(2))`B. `(1)/(2)n_(0)((1-f^(2))/(f))`C. `n_(0)((1-f)/(1+f))`D. `(1)/(2)n_(0)((1-f)/(1+f))` |
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Answer» Correct Answer - B |
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| 18. |
For the circuit shown, the ammeter reading is initially I. The switch in the circuit then is closed. Consequently (Battery and ammeter are ideal) A. the ammeter reading decreasesB. the potential difference between E and F increasesC. the potential difference between E and F stays the sameD. bulb 3 lights up more brightly. |
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Answer» Correct Answer - C Since FCD shorts bulb 3, the circuit I equivalently wires BC and EF in parallel. As the voltage across each branch must be equal to the voltage of the battery, the voltage from E to F is unchanged by closing the switch. Initially, there is voltage across the switch and after it is closed, the voltage is across the resistor. By closing the switch, the current in the circuit increases as effective resistance a cross battery decreases. (across battery effective resistance `=R_(1)/(1+(R_(1)//R_(2)) lt R_(1)` and the power from the battery must increase. |
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| 19. |
The waves produced during earthquake, ocean waves are known as: (a) audible waves (b) infrasonic waves (c) ultrasonic waves (d) mechanical waves |
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Answer» (b) infrasonic waves |
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| 20. |
The end correction of a resonance column is 2.0 cm. If the shortest length resonating with the tuning fork is 20.0 cm , the next resonating length will beA. 31 cmB. 45 cmC. 50 cmD. 64 cm |
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Answer» Correct Answer - D As `(lambda)/(4)=l_(1)+e` and `(3lambda)/(4)=l_(2)+e` `rArr (l_2+e)/(l_1+e)=3` `rArr l_(2)=3l_(1)+2e=3xx20+2xx2=64cm` |
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| 21. |
In a resonance column experiment the frequency of tuning fork used is `1000Hz` and the length of pipe is `100m`. Ignoring end correction find the length (in cm) of air column at which second resonance is observed. [Take speed of sound `=330m//s`] |
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Answer» Correct Answer - `00024.75` `00024.75` `f=(3v)/(4l)=1000impliesl=24.75cm` |
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| 22. |
In each of the following questions, a short passage is given with one of the lines in the passage missing and represented by a blank. Select the best out of the five answer choices given, to make the passage complete and coherent (coherent means logically complete and sound) Aggregation of risks is somewhat quite new to banks in India. While some banks have started thinking in that line by trying to put integrated limits framework and integrated risk policies as well as using CBS solutions for technological integration, the effort required is beyond such requirement. Risk aggregation would mean aggregating the individual risk measures to decide most appropriate assets class that would contain the risk to the desired level dicated by the risk appetite. Captial allocation (about how much) would be based on such strategies................A. Most banks are yet to conceptualize the same in their processesB. Most banks have already integrated it in their functioning, it is working over the years satisfactorily.C. Which would in long run prove to be the growth impedingD. Of risk aggregation which is really a new concept to Indian banks. |
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Answer» Correct Answer - D Capital allocation (about how much) would be based on such strategies of risk aggregation which is really a new concept to Indian banks. |
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| 23. |
In each of the following questions a short passage is given with one of the lines in the passage missing and represented by a blank. Select the best out of the five answer choices given, to make the passage complete and coherent. But no depreciation is allowed on Live Stock i.e. Horses. Although the horses are in the nature of fixed assets in the hands of the owner, no depreciation is allowed under income tax act. Instead when the animal dies or becomes permanently useless the entire value of the horse can be written off as revenue loss in year in which in dies or becomes permanently useless. When the gross income exceeds the total expenditure, it results in net profit which will be taxable at usual rates of tax applicable to the person. ________Although the live stock is in the nature of fixed assets of the owners buy them, maintain them, train them, and participate in races and Sell then or send them away to studs when they are useless.A. But when the gross income is less than the expenditure, then results it in lossB. But when the gross income is higher than the expenditure, then results in lossC. But when the gross income is equal to expenditure then result is lossD. But when the gross income is there loss is the result But when the gross income is increasing then result is becoming evident |
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Answer» Correct Answer - A It is the only logical option among the other options that do not follow anylogic. If income is less than expenditure, then there is definitely a loss. |
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| 24. |
In each of the following questions a short passage is given with one of the lines in the passage missing and represented by a blank. Select the best out of the five answer choices given, to make the passage complete and coherent. Aggregate of risks is somewhat quite new to banks in India. While some banks have started thinking in that line by trying to put integrated limits framework and integrated risk policies as well as using CBS solutions for technological integration, the effort required is beyond such requirement. Risk aggregation would mean aggregating the individual risk measures to decide most appropriate assets class that would contain the risk to the desired level dicated by the risk appetite. Capital allocation (about how much) would be based on such strategies_______A. Most banks are yet to conceptualize the same in their processesB. Most banks have already integrated it in their functioning, it is working over the years satisfactorily.C. Which would in long run prove to be the growth impedingD. Of risk aggregation which is really a new concept to Indian banks. |
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Answer» Correct Answer - A As the passage says that risk aggregation is new at the beginning of passage it can be inferred that most banks are yet to conceptualize it in their processes., Hence option (a) is correct. Option (c) is farfetched conclusion. Option (d) is repetition of what is being stated in passage earlier. So it cannot be the answer |
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| 25. |
In each of the following questions a short passage is given with one of the lines in the passage missing and represented by a blank. Select the best out of the five answer choices given, to make the passage complete and coherent. Whether the Government is right in bailing out a private sector bank is an issue that is decided more than by the long term social security policy of the Govenment, than by economic reasons alone______ Nevertheless, in a situation of scarcity of resources, bailing out somebody means the denial of resources to others. The irony of it is that in performing its duties of proper governance to the larger society through the process of bailing out, Government excuses the lack of corporate governance in banks.A. Economists world over learnt it hard way during the Great depressionB. This is elementary principle of economics taught in schoolsC. Reasons are not limited to these two but extend to debts, liquidity & credit ratings issuesD. It was unexpected and came like a bolt from the blue |
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Answer» Correct Answer - A Only option (a) seems to be logical for the context. As subsequent part of passage shows how it was a problem to bail out one and to deny other the same resources. Option (d) and (e) are out of place. |
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| 26. |
In each of the following questions a short passage is given with one of the lines in the passage missing and represented by a blank. Select the best out of the five answer choices given, to make the passage complete and coherent (choherent means logically complete and sound) By calling for exempting unionized business from the minimum wage, unions are creating more incentives for employers to favor unionized workers over the nonunionized sort. Such exemptions strengthen their power.___ Once employers are obliged to pay the same minimum wage to both unionized and non-unionized labor, workers often see less reason to pay the dues to join a union.A. High rates of unionization make minimum-wage rules unnecessary as collaborative wage setting achieves the flexibility goals of a low minimum wage and the fairness goals of a high one.B. Workers who have no real alternative to employment in the unregulated shadows of the labor market are even more vulnerable to exploitation and abuse than workers with the legal right to take low wages.C. The labor ethos of worker solidarity seems hollow if non-union workers are underpriced by union workers and left unemployed or scrambling for unauthorized work.D. This is useful because for all the effort unions throw at raising the minimum wage, laws for better pay have an awkward habit of undermining union clout. |
| Answer» Correct Answer - D | |
| 27. |
Calculate the root mean square speed of 1 mole of hydrogen molecules at 253k. Neglet the mass of electron |
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Answer» Molar mass of hydrogen gas, M = 2 x 10-3kg/mol R = 8.34 universal gas constant. root mean square velocity Vrms = \(\sqrt{\frac{3RT}{M}}\) = \(\sqrt{\frac{3\times 8.31\times 253}{2\times 10^{-3}}}\) = \(\sqrt{3153.64\times 10^3}\) = \(\sqrt{315.36\times 10^4}\) Vrms = 17.75 x 102m/s |
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| 28. |
P-V plots for two gases during adiabatic processes are shown in the figure. Plots 1 and 2 should corresponds respectively to A. He and `O_(2)`B. `O_(2)` and HeC. He and ArD. `O_(2) and N_(2)` |
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Answer» Correct Answer - B |
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| 29. |
Two simple pendulum with heavy bobs-one using iron wire and the other aluminimum wire are excited simultaneously. It is found that when the first pendulum completes 1000 oscillations the other completes 1001. When the temperature is raised by `t^(@)C`, it is found that the two pendulums now oscillate together. If he coefficients of thermal expansion of iron and aluminimum are `10 xx 10^(-6)//^(@)C` and `30 xx 10^(-6)//^(@)C` then the value of t is :A. `77.2^(@)C`B. `123.2^(@)C`C. `100.1^(@)C`D. `105.2^(@)C` |
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Answer» Correct Answer - C At lower temperature let the time period of the two pendulums be `T_(1)` & `T_(2)` `1000 T_(1)=1001 T_(2)` or `1000 sqrt(l)=1001 sqrt(l_(2))` At higher temp `l_(1)(1+alpha_(1)t)=l_(2)(1+alpha_(2)t)` `(l_(1))/(l_(2))=(1+alpha_(2)t)/(1+alpha_(1)t)` `:. ((1001)/(1000))^(2)=(1_30 xx10^(-6)t)/(1+10 xx10^(-6)t)rArr t = 100.1^(@)C`. |
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| 30. |
A steel wire of length 60 cm and area of cross section `10^(-6)m^(2)` is joined with a n aluminimum wire of length 45 cm and are of cross section `3xx10^(-6)m^(2)`. The composite string is stretched by a tension of 80 N. Density of steel is `7800kgm^(-3)` and that of aluminimum is `2600kgm^(-3)` the minimum frequency of tuning fork. Which can produce standing wave in it with node at joint isA. 357.3HzB. 375.3 HzC. 337.5 HzD. 325.3 Hz |
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Answer» Correct Answer - C Mass per unit length `mu=(m)/(l)=(rhoAl)/(l)=rhoA` `mu_(s)=mu_(Al)=78xx10(-4)kg//m` `therefore` speed of wave is same both wire `V=sqrt((T)/(mu))=sqrt((80xx10^(4))/(78))=(2xx10^(2))/(sqrt(3.9))` `v_(min)=(V)/(lamda_(max))=(200)/(sqrt(3.9)xx0.3)[(lamda_(max))/(2)=15cm" for C as a node"] =337.5Hz` |
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| 31. |
A cubical frame is made by connecting 12 identical uniform conducting rods as shown in the figure. In the steady state the temeprature of junction A is `100^(0)C` while that of the G is `0^(0)C`. ThenA. B will be Hotter than HB. Temperature of F is `40^(0)C`C. Temperature of D is `66.67^(0)C`D. Temperature of E is `50^(0)C` |
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Answer» Correct Answer - B `100^(@)C-lr-(l)/(2)r-lr=0^(@)C` `implieslr=40^(@)C,thereforet_(F)=0^(@)+lr=40^(@)C` |
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| 32. |
The figure shows a system of two concentric spheres of radii `r_1 and r_2` are kept at temperature `T_1 and T_2`, respectively. The radial rate of flow of heat in a substance between the two concentric spheres is proportional to A. `(r_(1)r_(2))/(r_(2)-r_(1))`B. `(r_(2)-r_(1))`C. `((r_(2)-r_(1)))/(r_(1)r_(2))`D. `log_(e)((r_(2))/(r_(1)))` |
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Answer» Correct Answer - A `H=-k4pir^(2)(dT)/(dr)impliesHprop(r_(1)r_(2))/(r_(2)-r_(1))` |
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| 33. |
A body of mass `1kg` is suspended from a weightless spring having force constant `600N//m`. Another body of mass `0.5 kg` moving vertically upward hits the suspended body with a velocity of `3.0m//s` and get embedded in it. Find the frequency of oscillations and amplitude of motion.A. `(10)/(pi)Hz,10Cm`B. `(10)/(pi)Hz,5Cm`C. `(5)/(pi)Hz,5Cm`D. `(5)/(pi)Hz,10Cm` |
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Answer» Correct Answer - B `V=(0.5xx3)/((0.5+1))=1m//simpliesK_(max)=U_(max)` `(1)/(2)xx1.5xx1^(2)=(1)/(2)xx600xxA^(2)` `A=5cm` `f=(1)/(2pi)sqrt((k)/(m))=(1)/(2pi)sqrt((600)/(1.5))=(10)/(pi)` `f=(10)/(pi)Hz` |
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| 34. |
Two astronauts are floating in gravitational free space after having lost contanct with their spaceship. The two will:A. keep floating at the same distance between themB. move towrds each otherC. move away from each otherD. will become stationary |
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Answer» Correct Answer - B |
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| 35. |
Which of following statements are correct ? ltbgt(a) Centre of mass of a body always coincides with the centre of gravity of the body (b) Central of mass of a body is the point at which the total garvitational torque on the body is zero (c ) Couple on a body produces both trasnlational and rotation motion in a body (d) Mechinical advantage greater than one means that small efforts can be used to lift a large loadA. (2) and (4)B. (1) and (2)C. (2) and (3)D. (3) and (4) |
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Answer» Correct Answer - B |
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| 36. |
A U-tube with both ends open to the atmosphere is partially filled with water. Oil, which is immiscible with water. Is poured into one side until it stands at a distance of `10 mm` above the water level on the other side. Meanwhile the water rises by `65mm` from its original level (see diagram). The density of the oil is: A. `650 kg m^(-3)`B. `425 kg m^(-3)`C. `800 kg m^(-3)`D. `928 kg m^(-3)` |
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Answer» Correct Answer - D |
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| 37. |
A small block is connected to one end of a massless spring of un - stretched length `4.9 m`. The other end of the spring (see the figure) is fixed. The system lies on a horizontal frictionless surface. The block is stretched by `0.2 m` and released from rest at `t = 0`. It then executes simple harmonic motion with angular frequency `(omega) = (pi//3) rad//s`. Simultaneously at `t = 0`, a small pebble is projected with speed (v) from point (P) at an angle of `45^@` as shown in the figure. Point (P) is at a horizontal distance of `10 m from O`. If the pebble hits the block at `t = 1 s`, the value of (v) is `(take g = 10 m//s^2)`. .A. `sqrt(50) m//s`B. `sqrt(51) m//s`C. `sqrt(52) m//s`D. `sqrt(53) m//s` |
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Answer» Correct Answer - A Time of flight for projectile `T = (2u sin theta)/(g) = 1 sec` `(2u sin 45)/(g) =1 sec` `u = (g)/(sqrt(2))` `u = sqrt(50) m//s`. |
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| 38. |
The frequency of an infrasonic wave is: (a) 20 Hz (b) below 20 Hz (c) above 20 Hz (d) above 20 KHz |
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Answer» Correct answer is (b) below 20 Hz |
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| 39. |
A simple pendulum is oscillating without damiping, When the displacement of the bob is less than maximum, its acceleration vector `veca` is correctly show in:A. B. C. D. |
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Answer» Correct Answer - C |
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| 40. |
An ideal gas expands according to the law `PV^(3//2)`=constant We conclude thatA. the adiabatic exponent of the gas k=1.5B. the molar heat capacity `C=C_(V)-2R`C. temperature increases during the processD. such a gas is not feasible. |
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Answer» Correct Answer - B `C=C_(V)+(PdV)/(ndT)` `PV^(3//2)=k," "PV=nRT` Find relation in V and T `(dV)/(dT)=-(2V)/(T)` `thereforeC=C_(V)-2R` |
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| 41. |
In which type of collector is solar radiation focused into the absorber from the top, rather than from the bottom? (a) Fresnel lens (b) Paraboloidal (c) Concentrating (d) Compound parabolic |
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Answer» (a) Fresnel lens |
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| 42. |
The fig. shows the variation of photon current with anode potential for a photo-sensitive surface for three different radiation. Let `I_(a), I_(b) and I_(c)` be the intensities and `f_(a), f_(b) and f_(c)` be the frequency for the curves a,b and c respectively. A. `f_(a) = f_(b), l_(a) != l_(b)`B. `f_(a) = f_(c ), l_(a) = l_(c )`C. `f_(a) = f_(b), l_(a) = l_(b)`D. `f_(b) = f_(c), l_(b) = l_(c )` |
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Answer» Correct Answer - A stopping potential for a and b are same. Hence `f_(a)=f_(b)` but current `l_(b)` is more than `l_(r )` at zero potential |
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| 43. |
Lead is a good absorber of X rays. Specific gravity of `Pb = 11.5`. To cut down the initial radiation `l_(0)` to `(l_(0))/(2)` a shield of `1.5 cm` was used. The mass absorption co-efficient isA. `0.06 cm^(2)//g`B. `0.462 cm^(-1)`C. `0.21 cm^(-1)`D. `0.040 cm^(2)//g` |
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Answer» Correct Answer - B `l_(2)=l_(0)(1-e^(-mux)) l=(l_(0))/(2), x=1.5 cm^(-1)` `mu = 0.462 cm^(2)lg` |
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| 44. |
As shown in figure process AB is isobaric, BC is adiabasic CD is isochoric and DA is isothermal, through which n-moles of monoatomic gas undergo a cyclic process. The max & min temperature in the cycle are `4T_(0)` and `T_(0)` respectively.A. `T_(B)` is greater than `T_(D)`B. Heat is released by gas in the process CDC. Heat is supplied to the gas in the process ABD. `T_(C)` is greater than `T_(A)` |
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Answer» Correct Answer - A::B::C::D DA is isothermal `becauseT_(D)=T_(A)` `TalphaPV` from graph `(PV)_(C)gt(PV)_(D)` BC is adiabatic expansion so, `T_(B)gtT_(C)` so `T_(B)gtT_(D)` and `T_(B)gtT_(A)` maximum temperature at B or C and minimum temperature at D or A. `T_(B)=4T_(D)` `T_(D)=T_(A)=T_(B)` IN process `CD:DeltaW=0,DeltaQ=DeltaU` pressure is decreasing, volume is constant. Temperature and intenal energy will decrease. `DeltaQ=-ve`, heat is released in CD. In `AB,DeltaQ=nC_(P)DeltaT` Volume is increasing and pressure is constant, temperature will increase `DeltaQ` is positive so, heat is supplied to the gas in process AB. |
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| 45. |
The effect that makes 2,3-dimethyl-2-butene more stable than 2-butene is :A. hyperconjugationB. reseonceC. steric effectD. inductive effect |
| Answer» Correct Answer - A | |
| 46. |
`n` moles of a monoatomic gas undergoes a cyclic process ABCDA as shown. Process AB is isobaric, process BC is adiabatic process CD is isochoric and process DA is isothermal the maximum temperature and minimum temperature in cycle are `4T_(0)` and `T_(0)` respectively. Then:A. `T_(B)gtT_(C)gtT_(D)`B. heat is released by the gas in the process `CD`C. geat is supplied by the gas to the surrounding in the process ABD. heat is supplied to the gas to the surrounding in the process AB |
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Answer» Correct Answer - A::B::D `BC` is adiabatic `TV^(r-1)=` constant `VuarrTdarr` CD is isochoric `V=` constant `PpropT` `PdarrTdarr` AB is isobaric `P=` constant `DeltaQ=DeltaU+DeltaW` `DeltaU=+ve` `DeltaW=+ve` `DeltaQ=+ve`. |
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| 47. |
Two moles of an ideal gas goes under the process shown in figure. AB and CD are reversible adiabatic process. The gas under the process isA. MonoatomicB. DiatomicC. Non linear polyatomicD. Mixture of mononoatmic and non-linear polyatomic |
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Answer» Correct Answer - A `PV^(gamma) =` constant `P_(0) (2V_(0))^(gamma) = (P)/(32) (16V_(0))^(gamma)` `P_(0)V_(0)^(gamma) 2^(gamma) = PV_(0)^(gamma) (16^(gamma))/(32)` `2^(gamma) = (2^(4_(gamma)))/(2^(5))` `2^(5) = 2^(3_(gamma))` `5 = 3^(gamma)` `rho = 5//3` monoatomic gas. |
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| 48. |
Two moles of an ideal gas goes under the process shown in figure. AB and CD are reversible adiabatic process. The efficiency of the cycle isA. `1//4`B. `1//2`C. `3//4`D. `3//5` |
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Answer» Correct Answer - C `Q_(DA) = nCP (T_(A) - T_(D))` `= 2 xx Cp ((P_(0) xx V_(0))/(2R) - (P_(0)v_(0))/(2R))` `= 2Cp ((P_(0)V_(0))/(2R))` `Q_(BC) = 2Cp ((P_(0))/(32) xx (8V_(0))/(2R) - (P_(0))/(32) xx (16V_(0))/(2R))` `= - 2Cp ((P_(0)V_(0))/(8R))` (Negative sign shows loss in heat) `eta = 1 - (Q_(BC))/(Q_(DA)) = (3)/(4)` |
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| 49. |
The efficiency of the reversible cycle shown in the given figure is A. `33.33%`B. `56%`C. `66%`D. `16.7%` |
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Answer» Correct Answer - A `"Efficiency" = ("Area bounded by the curve")/("Total area under the line BC") xx 100` |
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| 50. |
For induction of alien DNA in host cell we may use- (A) Gene (B) Micro -pipette (C) Both (A) & (B) (D) None of these |
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Answer» For induction of alien DNA in host cell we may use Gene. |
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