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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.
| 501. |
The concentration of a substance undergoing a chemical reaction becomes one-half of its original value after time t regardless of the initial concentration. The reaction is an example of a -A. zero order reactionB. first order reactionC. second order reactionD. third order reaction |
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Answer» Correct Answer - B Informative |
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| 502. |
Reaction of 2- butene with acidic `KMnO_(4)` givesA. `CH_(3) CHO`B. `HCOOH`C. `CH_(3)CH_(2) OH`D. `CH_(3)COOH` |
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Answer» Correct Answer - D `CH_(3) -CH=CH-CH_(3) underset( "Oxidi sing agent ")overset(KMnO_(4)) to CH_(3) COOH ` |
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| 503. |
The order of electronegativity of carbon in sp, `sp^(2) and sp^(3)` hybridized states followsA. `spgtsp^(2)gtsp^(3)`B. `sp^(3)gtsp^(2)gtsp`C. `spgtsp^(3)gtsp^(2)`D. `sp^(2)gtspgtsp^(3)` |
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Answer» Correct Answer - A Electronegativity `prop%` s character `{:(CH_(3)-CH_(3),lt,CH_(2)=CH_(2),lt,CH-=CH,),(" "sp^(3),," "sp^(2),," "sp,),(25%"s character",,33.%"s character",,50%"s character",):}` |
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| 504. |
If a, b, c, d are positive real numbers such that `(a)/(3)=(a+b)/(4)=(a+b+c)/(5)=(a+b+c+d)/(6),"then"(a)/(b+2c+3d)` is-A. 1//2B. 1C. 2D. Not determinable |
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Answer» Correct Answer - A `(a)/(3)=(a+b)/(4)=(a+b+c)/(5)=(a+b+c+d)/(6)=k` a=3k, b=k, c=k, d=k Hence:- `(a)/(b+2c+3d)=(3k)/(k+2k+3k)=(1)/(2)` |
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| 505. |
For `(2^(2)+4^(2)+6^(2)+.......+(2n)^(2))/(1^(2)+3^(2)+......+(2n-1)^(2))` to exceed 1.01, the maximum value of n is-A. 99B. 100C. 101D. 150 |
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Answer» Correct Answer - D `(2^(2)(1^(2)+2^(2)+3^(2)+......+n^(2)))/[[1^(2)+2^(2)+3^(2)+.......+(2n)^(2)]-2^(2)(1^(2)+2^(2)+3^(2)+.....n^(2)))` `((2^(2)n(n+1)(2n+1))/(6))/((2n(2n+1)(4n+1))/(6)-(2^(2)n(n+1)(2n+1))/(6))gt1.0` `(2n+2)/(2n-1)gt1.01` `1+(3)/(2n-1)gt1.01` `2n-1gt300` `nlt150.5` |
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| 506. |
The sum of `(1^(2)-1+1) (1!)+(2^(2)-2+1)(2!) +...+ (n^(2)-n+1) (n!)` is -A. `(n+2)!`B. `(n-1)((n+1)!)+1`C. `(n+2)!-1`D. `n((n+1)!)-1` |
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Answer» Correct Answer - B `T_(n)=(n^(2)-n+1)n!` `=(n^(2)-1)n!-(n-2)n!` `T_(n)=(n-1)(n+1)!-(n-1)n!` Sum `=1+(n-1) (n+1) !` |
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| 507. |
The minimum value of n for which `(2^(2)+4^(2)+6^(2)+...+(2n)^(2))/(1^(2)+3^(2)+5^(2)+...+(2n-1)^(2)) lt 1.01`A. is 101B. is 121C. is 151D. does not exist |
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Answer» Correct Answer - C `x/((2n(2n+1)(4n +1))/(6)-x) lt 1.01` `2.01x lt (1.01) (2n(2n+1)(4n+1))/(6)` `2.01. (4n(n+1)(2n+1))/(6) lt (1.01) (2n(2n+1)(4n+1))/(6)` `2.01/1.01 lt (4n+1)/(2n+2) rArr n gt 150.5` |
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| 508. |
Let X be be a ninempty set and let P(X) denote the collection of all subsets of X. Define `f : X xx P(X) rarr` by `f(x, A)={(1",",if,x in A),(0",",if,x notin A):}` Then `f(x, A uu B)` equals-A. `f(x, A)+f(x, B)`B. `f(x, A)+f(x, B)-1`C. `f(x, A)+f(x, B)-f(x, A) f(x, B)`D. `f(x, A)+|f(x, A)-f(x, B)|` |
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Answer» Correct Answer - C `f(x, A uuB)={(1,if,x in A uu B),(0,if,x notin A uu B):}` `{:(if,x in A",",x in B),(if,x in A",",x notinB),(if,x notin A",",x in B):}} {:(rArr f(x, A uu B)=1rArr" None of the option (A, B, D) satisfy"),(),():}` if `x notin A, x notin B rArr f(x, A uu B)=0 rArr C("only C satisfy")` |
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| 509. |
A 100 mark examination was administered to a class of 50 students. Despite only integer marks being given, the everge score of the class was 47.5. Then , the maximum number of students who could get marks more than the class average isA. 25B. 35C. 45D. 49 |
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Answer» Correct Answer - D Total students =50 Average =47.5 Total marks = 2375 Now, student can obtain only integer marks. Hence for maximum students we will total marks by `48^(@)rArr[2375/48]=49` |
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| 510. |
Let PQR be am acute-angled triangle in which PQ lt QR. From the vertex Q draw altitude `QQ_(1)`, the angle bisector `Q Q_(2)` and the median`Q Q_(3)" With "Q_(1),Q_(2),Q_(3)` lying on PR. Then A. `PQ_(1)ltPQ_(2)ltPQ_(3)`B. `PQ_(2)ltPQ_(1)ltPQ_(3)`C. `PQ_(1)ltPQ_(3)ltPQ_(2)`D. `PQ_(3)ltPQ_(1)ltPQ_(2)` |
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Answer» Correct Answer - A `PQ_(3)=Q_(3)R( :. Q Q_(3)" ie median")` `PQ_(3)=1/2PR` `PQ_(2):Q_(2)R=r:p" (By peoperty of angle bisector)"` `PQ_(2)=(r/(r+P))PR` But r lt P (Given) `PQ_(2)lt1/2PR` Comparison between Altitude and angle bisector `rArr angleQPQ_(2)+anglePQ_(2)Q+anglePQ Q_(2)=angle RQ Q_(2)+angleQ Q_(2)R+angleQRQ_(2)` `:. anglePQ Q_(2)+angleRQ Q_(2)" {Since angle bisector}"` `angle QPQ_(2)+anglePQ_(2)Q=angle Q Q_(2)R+angleQRQ_(2)` `:.PQltQR" then"ltQPQ_(2)gtangle QRQ_(2)` Hence `angleQ Q_(2)P+ltangleQ Q_(2)R` But `angle Q Q_(2)P+angleQ Q_(2)R=180^(@)` Hence `angle Q Q_(32)Plt90^(@)&angle Q Q_(2)Rgt 90^(@)` `rArr" Foot from Q to side PR lies inside "DeltaPQ Q_(2)` `rArrPQ_(1)lt PQ_(2)ltPQ_(3)` |
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| 511. |
A solid hemisphere is attached to the top of a cylinder, having the same radius as that of the cylinder. If the height of the cylinder were doubled (keeping both radii fixed), the volume of the entire system would have increased by 50%. By what percentage would the volue have increased if the radii of the hemisphere and the cylinder were doubled (keeping the height fixed)?A. 3B. 4C. 5D. 6 |
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Answer» Correct Answer - C Let hight of radius of cylinder are h & r respectively. Then volume `V_(1)=pir^(2)h+2/3pir^(3)" …(1)"` When height of cylinder is doubled then volume `V_(2)=pir^(2)h+2/3pir^(3)" …(2)"` Given that `(V_(2))/(V_(1))=3/2rArr(2h+(2)/(3)r)/(h+2/3r)=3/2` `rArr2h+2/3r=3/2h+r` `rArrh/2=r/3rArrh=2/3r" ...(3)"` When radius is doubled then volume `V_(2)^(1)=4pir^(2)h+16/3pir^(3)` `(V_(2)^(1))/(V_(1))=(4h+16/3r)/(h+2/3r)` By `(3)(V_(2)^(1))/(V_(1))=(4h+8h)/(h+h)=6` Hence volume will be increased by 500% |
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| 512. |
Let f(x) = x12 – x9 + x4 – x + 1. Which of the following is true ? (A) f is one-one (B) f has a real root (C) f ′ never vanishes (D) f takes only positive values |
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Answer» Correct Option :- (D) f takes only positive values Explanation :- f(x) = x9 (x3 – 1) + x (x3 – 1) + 1 positive for x ≥ 1 or x ≤ 0 = 1 – x + x4 – x9 + x12 positive for x∈(0, 1) f(x) is always positive |
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| 513. |
Suppose a, b are real numbers such that `ab ne 0`. Which of the following four figures represents the curve `(y -ax - b)(bx^(2) + ay^(2) - ab) = 0` ?A. B. C. D. |
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Answer» Correct Answer - B `y = ax + b` and ` (x^(2))/(a) + (y^(2))/(b) = 1` slope `=a` for the line, y intercept `= b` Fig 1. for line `rarr a lt 0, b gt 0` hence the other fig. Cannot be an ellipse Fig.2 `a gt 0, b lt 0` hence the fig. is a hyperbola Similarly you can check rest 2 options |
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| 514. |
Which of the following statements is true about the flow of electrons in an electric circuit ?A. Electrons always flow from lower to higher potentialB. Electrons always flow from higher to lower potentialC. Electrons flow from lower to higher potential except through power sourcesD. Electrons flow from higher to lower potential, except through power sources |
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Answer» Correct Answer - C |
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| 515. |
A convex lens of focal length 15 cm is placed in front of a plane mirror at a distance 25 cm from the mirror. Where on the optical axis and from the centre of the lens should a small object be placed such that the final image coincides with the object ?A. 15 cm and on the opposite side of the mirrorB. 15 cm and between the mirror and the lensC. 7.5 cm and on the opposite side of the mirrorD. 7.5 cm and between the mirror and the lens |
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Answer» Correct Answer - A |
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| 516. |
Following figures show different combinations of identical bulb(s) connected to identical battery(ies). Which option is correct regarding the total power dissipated in the circuit– A. PltQltRltSB. PltQltR=SC. RltQltPltSD. PltRltQltS |
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Answer» Correct Answer - D |
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| 517. |
Particles used in the Rutherford’s scattering experiment to deduce the structure of atomsA. had atomic number 2 and were fully ionised.B. had atomic number 2 and were neutral.C. had atomic number 4 and were fully ionised.D. had atomic number 4 and were neutral. |
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Answer» Correct Answer - A |
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| 518. |
The number of completely filled shells for the element `._(16)S^(32)` isA. 1B. 2C. 3D. 4 |
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Answer» Correct Answer - B |
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| 519. |
Which fo the following is secreted at the ends of an axon?A. Ascorbic acidB. Acetic acidC. Acetyl cholineD. Acetyl CoA |
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Answer» Correct Answer - C Synaptic bulbs of axon have vesicles which are filled with acetylcholine. |
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| 520. |
Rhinoviruses are the causative agents ofA. DiarrhoeaB. AIDSC. DengueD. Common cold |
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Answer» Correct Answer - D Rhinovirus are the primary causes of cammon cold. |
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| 521. |
A bacterial colony is produced fromA. a single bacterium by its repetitive divisionB. multiple bacterium without replicationC. clumping of two to three bacteriaD. a single bactgerium whithout cell division |
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Answer» Correct Answer - A A bacterial colony on culture media is formed on repetitive division of bacterium. |
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| 522. |
The oxidation states of P atom in `POCl_(3),H_(2)PO_(3)" and "H_(4)P_(2)O_(6),` respectively, areA. +5, +4, +4B. +5, +5, +4C. +4, +4, +5D. +3, +4, +5 |
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Answer» Correct Answer - A `O.No"."` `POCl_(3)" "+5` `H_(2)PO_(3)" "+5` `H_(4)P_(2)O_(6)" "+4` |
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| 523. |
The solubility curve of `KNO_(3) ` in water is shown below. The amount of `KNO_(3)` that dissolves in 50 g of water at ` 40^(@)C` is closest toA. 100 gB. 150 gC. 200 gD. 50 g |
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Answer» Correct Answer - A At ` 40^(@)C` solubility is 200 gm per 100 ml (approx) i.e., 100 ml of water contains = 200 gm of `KNO_(3)` (approx) 50 ml of water contains = 100 gm (approx) |
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| 524. |
In the conversion of zinc ore to zinc metal, the process of roasting involesA. `ZnCO_(3) to ZnO`B. `ZnO to ZnSO_(4)`C. `ZnS to ZnO`D. `ZnS to ZnSO_(4)` |
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Answer» Correct Answer - C `2 ZnS+3O_(2) overset(950^(@)C) to 2 ZnO+2 SO_(2)` `ZnS+2O_(2) overset(950^(@)C) toZnSO_(4)` `" then "2 ZnSO_(4) overset(950^(@)C) to 2 ZnO+2 SO_(2)+O_(2)` |
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| 525. |
After 2 hours the amount of a certain radioactive substance reduces to `1//16^(th)` of the original amount (the decay process follows first-order kinetics). The half-life of the radioactive substance isA. 15 minB. 30 minC. 45 minD. 60 min |
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Answer» Correct Answer - B `(0.693)/(t_(1//2))=(2.303)/(2xx60)log. (a)/(a//16)` `t_(1//2)=30 min` |
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| 526. |
The quantity of heat (in J) required to raise temperature of 1.0 kg of ethanol from 293.45 K to the boiling point and then change the liquid to vapor at that temperature is closest to [Given , Boiling point of ethanol 351.45K] Specific heat capacity of liquid ethanol `2.44Jg^(-1)K^(-1)` latent heat of vaporization of ethanol `855Jg^(-1)K^(-1)`A. `1.42xx10^(2)`B. `9.97xx10^(2)`C. `1.42xx1^(5)`D. `9.97xx10^(5)` |
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Answer» Correct Answer - D `q=mc Deltat+"heat of vapourisation"` `=100xx2.44(351.45-293.45)+855xx1000J` `=9.97xx10^(5)J` |
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| 527. |
`50 mL` of `0.1 M` solution of sodium acetate and `50 mL` of `0.01 M` acetic acid mixed. The `pK_(a)` of acetic acid is `4.76`. The `P^(H)` of the buffer solution isA. `4.26`B. `5.76`C. `3.76`D. `4.76` |
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Answer» Correct Answer - D `"Meq of "CH_(3)COOH=100 xx0.1xx1=10` `" Meq of " CH_(3)COONa = 50xx 0.2 xx 1 = 10` `pH=pK_(a)+log. ([CH_(3)COO^(-)])/([CH_(3)COOH])` `pH=4.76+log. 10/10` `pH=4.76+log 1` `pH=4.76` |
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| 528. |
In a closed vesselm an ideal gas at 1 atm is heated from ` 27^(@) C "to" 327^(@)C`. The pressure of gas will approximately beA. 3 atmB. 0.5 atmC. 2 atmD. 12 atm |
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Answer» Correct Answer - c `P propT( V, n to const)` `P_(1)/P_(2)=T_(1)/T_(2)` `1/P_(2)= 300/600` `P_(2)=2atm` |
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| 529. |
Among the elements Li, N ,C and Be one with the largest atomic radius idA. LiB. NC. CD. Be |
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Answer» Correct Answer - a as er move left to right in a period atomic radius decrease rdue to increase in `Z_("eff")` so , greatest radius is of lithium. |
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| 530. |
A closed pipe of length 300 cm contains some sand. A speaker is connected at one of its ends. The frequency of the speaker at which the sand will arrange itself in 20 equidistant piles is close to (velocity of sound is 300 m/s) A. 10 kHzB. 5 kHzC. 1 kHzD. 100 kHz |
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Answer» Correct Answer - C |
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| 531. |
A bomb explodes at time t = 0 in a uniform, isotropic medium of density `rho` and releases energy E, generating a spherical blast wave. The radius R of this blast wave varies with time t as :A. tB. `t^(2//5)`C. `t^(1//4)`D. `t^(3//2)` |
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Answer» Correct Answer - B |
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| 532. |
Consider a plane parallel beam of light incident on a plano-cylindrical lens as shown below. Which of the following will you observe on a screen placed at the focal plane of the lens ? A. The screen will be uniformly illuminated.B. There will be a single bright spot on the screen.C. There will be a single bright line on the screen parallel to the x-axisD. There will be a single bright line on the screen parallel to the y-axis |
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Answer» Correct Answer - D |
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| 533. |
A small ring is rolling without slipping on the circumference of a large bowl as shown in the figure. The ring is moving down at `P_(1)`, comes down to the lower most point `P_(2)` and is climbing up at `P_(3)`. Let `vecv_(CM)` denote the velocity of the centre of mass of the ring. Choose the correct statement regarding the frictional force on the ring. A. It is opposite to `vecv_(CM)` at the points `P_(1), P_(2)` and `P_(3)`.B. It is opposite to `vecv_(CM)` at `P_(1)` and in the same direction as `vecv_(CM)` at `P_(3)`C. It is in the same direction as `vecv_(CM)` at `P_(1)` and opposite to `vecv_(CM)` at `P_(3)`.D. It is zero at the points `P_(1), P_(2)` and `P_(3)`. |
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Answer» Correct Answer - B |
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| 534. |
The n-side of the depletion layer of a p-n junction :A. always has same width as of the p-side.B. has no bound charges.C. is negatively charged.D. is positively charged. |
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Answer» Correct Answer - D |
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| 535. |
A block of mass m is sliding down an inclined plane with constant speed. At a certain instant t0, its height above the ground is h. The coefficient of kinetic friction between the block and the plane is `mu`. If the block reaches the ground at a later instant `t_g`, then the energy dissipated by friction in the time interval `(t_(g)-t_(0))` is - A. `mu mgh`B. `mumg h// sin theta`C. mghD. `mumgh//cos theta` |
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Answer» Correct Answer - C |
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| 536. |
150 g of ice is mixed with 100 g of water at temperature `80^(@)C`. The latent heat of ice is 80 cal/g and the specific heat of water is `1 cal//g-.^(@)C`. Assuming no heat loss to the environment, the amount of ice which does not melt is –A. 100 gB. 0 gC. 150 gD. 50 g |
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Answer» Correct Answer - D |
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| 537. |
A circular loop of wire s in the same plane as an infinitely long wire carrying a constant current i. Four possible motions of the loop are marked by N, E, W, and S as shown. A clockwise current is induced in the loop when loop is pulled towardsA. NB. EC. WD. S |
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Answer» Correct Answer - B |
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| 538. |
A circular loop of wire s in the same plane as an infinitely long wire carrying a constant current i. Four possible motions of the loop are marked by N, E, W, and S as shown. – A clockwise current is induced in the loop when loop is pulled towards (A) N (B) E (C) W (D) S |
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Answer» Correct option (B) E Explanation: This is in accordance with Lenz's law |
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| 539. |
A body of 0.5 kg moves along the positive x-axis under the influence of a varying force F (in Newtons) as shown below. If the speed of the object at x = 4m in 3.16 `ms^(-1)` then its speed at x = 8m is A. `3.16ms^(-1)`B. `9.3 ms^(-1)`C. `8 ms^(-1)`D. `6.8ms^(-1)` |
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Answer» Correct Answer - D |
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| 540. |
The lower stability of ethyl anion compared to methyl anion and the higher stability of ethyl radical compared to methyl radical, respectively, are due to (A) +I effect of the methyl group in ethyl anion and σ → p-orbital conjugation in ethyl radical (B) –I effect of the methyl group in ethyl anion and σ → σ∗ conjugation in ethyl radical (C) +I effect of the methyl group in both cases (D) +I effect of the methyl group in ethyl anion and σ → σ∗ conjugation in ethyl radical |
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Answer» Correct option (A) +I effect of the methyl group in ethyl anion and σ → p-orbital conjugation in ethyl radical Explanation: Stability C2 H2− > CH3− In ethyl anion, methyl group have +I effect which increases e– density on carbanion so stability decreases. Stability C2 H5 > CH3 Due to σ –p orbital conjugation in ethyl radical, it is more stable. |
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| 541. |
A car goes around uniform circular track of radius R at a uniform speed v once in every T seconds. The magnitude of the centripetal acceleration is `a_(c)`. If the car now goes uniformly around a larger circular track of radius 2R and experiences a centripetal acceleration of magnitude `8a_(c)`, then its time period isA. 2TB. 3TC. T/2D. 3/2 T |
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Answer» Correct Answer - C |
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| 542. |
The primary and the secondary coils of a transformer contain 10 and 100 turns, respectively. The primary coil is connected to a battery that supplies a constant voltage of 1.5 volts. the voltage across the secondary coil is (A) 1.5 V (B) 0.15 V (C) 0.0 V (D) 15 V |
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Answer» Correct Option :- (C) 0.0 V Explanation :- Since the voltage production is based upon A.C. supply and this voltage is D.C which is constant. Therefore, no flux will change in secondary and no voltage will be induced. Answer is (C) 0V. |
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| 543. |
The length and width of a rectangular room are measured to be `3.95pm0.05` m and `3.05pm0.05` m, respectively, the area of the floor isA. `12.05pm0.01m^(2)`B. `12.05pm0.005m^(5)`C. `12.05pm0.34m^(2)`D. `12.05pm0.40m^(2)` |
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Answer» Correct Answer - C |
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| 544. |
A person walks `25.0^(@)` north of east for `3.18` km. How far would she have to walk due north and then due east to arrive at the same location?A. towards north `2.88` km and towards east `1.34` kmB. towards north `2.11` km and towards east `2.11` kmC. towards north `1.25` km and towards east `1.93` kmD. towards north `1.34` km and towards east `2.88` km |
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Answer» Correct Answer - D |
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| 545. |
The binding energy per nucleon of `._(5)B^(10)` is 8.0 MeV and that of `._(5)B^(11)` is 7.5 MeV. The energy required to remove a neutron from` ._(5)B^(11)` is (mass of electron and proton are `9.11xx10^(31)` kg and `1.67xx10^(27)` kg, respectively)A. 2.5 MeVB. 8.0 MeVC. 0.5 MeVD. 7.5 MeV |
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Answer» Correct Answer - A |
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| 546. |
The wavelength of the first Balmer line caused by a transition from the n = 3 level to the n = 2 level in hydrogen is `lamda_(1)`. The wavelength of the line caused by an electronic transition from n = 5 to n = 3 is -A. `(375)/(128)lamda_(1)`B. `(125)/(64)lamda_(1)`C. `(64)/(125)lamda_(1)`D. `(128)/(375)lamda_(1)` |
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Answer» Correct Answer - B |
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| 547. |
Two identical parallel plate capacitors of capacitance C each are connected in series with a battery of emf, E as shown. If one of the capacitors is now filled with a dielectric of dielectric constant k, the amount of charge which will flow through the battery is (neglect internal resistance of the battery) A. `(k+1)/(2(k-1))CE`B. `(k-1)/(2(k+1))CE`C. `(k-2)/(k+2)CE`D. `(K+2)/(k-2)CE` |
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Answer» Correct Answer - B |
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| 548. |
Let `vec(a)=6vec(i)-3vec(j)-6vec(k) and vec(d)=vec(i)+vec(j)+vec(k)."Suppose that" vec(a)=vec(b)+vec(c) "where" vec(b) "is parallel to" vec(d) and vec(c) " si perpendicular to" vec(d). "Then" vec(c) "is-"`A. `5vec(i)-4vec(j)-vec(k)`B. `7vec(i)-2vec(j)-5vec(k)`C. `4vec(i)-5vec(j)+vec(k)`D. `3vec(i)+6vec(j)-9vec(k)` |
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Answer» Correct Answer - B `vec(b)=lamda(hati+hat(j)+hat(k))` `vec(a)=vec(b)+vec(c)` `vec(c)=vec(a)-lamda (hati+hat(j)+hat(k))` `vec(c)=(6hat(i)-3hatj-6hatk)-lamda(hati+hat(j)+hat(k))` `vec(c)(6-lamda)hat(i)+(-3-lamda)hat(j)+(-6-lamda)hat(k)` `vec(c).vec(lamda)=6-lamda-3-lamda-6-lamda=0` `3lamda=3` `lamda=-1` `vec(c)=7hat(i)-2hat(j)-5hat(k)` |
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| 549. |
`"If" log_((3x-1))(x-2)= log_((9x^(2)-6x+1))(2x^(2)-10x-2)`, then x equals-A. `9-sqrt(15)`B. `3+sqrt(15)`C. `2+sqrt(5)`D. `6-sqrt(5)` |
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Answer» Correct Answer - B ` log_((3x-1))(x-2)= log_((3x-1))(2x^(2)-10x-2)` ` log_((3x-1))(x-2)^(2)= log_((3x-1))(2x^(2)-10x-2)` `(x-2)^(2)=2x^(2)-10x-2` `x^(2)-4x+4=2x^(2)-10x-2` `x^(2)-6x-6=0` `x=3+-sqrt(15)` `x=3-sqrt(15)" "x=3+sqrt(15)` `at 3-sqrt(15)` (x-2) is negative |
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| 550. |
`Let x=(sqrt(50)+7)^(1//3)-(sqrt(50)-7)^(1//3)`.Then-A. x=2B. x=3C. x is a rational number, but not an integerD. x is an irrational number |
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Answer» Correct Answer - A `x=(sqrt(50)+7)^(1//3)-(sqrt(50)+7)^(1//3)` `x^(3)=(sqrt(50)+7)-(sqrt(50)-7)-3(sqrt(50)+7)(sqrt(50)+7)^(1//3)-(sqrt(50)-7)-(sqrt(50)+7)^(1//3)` `x^(3)=14-3(1)(x)` `x^(3)=14-3x` `x^(3)+3-14=0` x=2 |
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