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.
| 21301. |
If the magnetic field of a plane electromagentic wave is given by (The speed of light = 3 × 108 m/s) B = 100 × 10–6 sin [2π x 2 x 1015(t - x/c)], then the maximum electric field associated with it is : (1) 4 × 104 N/C (2) 3 × 104 N/C (3) 6 × 104 N/C (4) 4.5 × 104 N/C |
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Answer» Correct option: (2) 3 × 104 N/C Explanation: E = CB E = 3 × 108 × 100 × 10–6 = 3 × 104 N/C |
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| 21302. |
To get output '1' at R, for the given logic gate circuit the input values must be : (1) X = 1, Y = 0 (2) X = 0, Y = 0 (3) X = 1, Y = 1 (4) X = 0, Y = 1 |
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Answer» Correct option: (1) X = 1, Y = 0 Explanation: By using concept of logic gates we will get X = 1, Y = 0 |
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| 21303. |
What group do the words belong to?1, 3, 5, 7 |
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Answer» Correct answer is odd numbers |
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| 21304. |
Match List I with List II:List IPollutantList IISourceA. MicroorganismsI. Strip miningB. Plant nutrientsII. Domestic sewageC. Toxic heavy metalsIII. Chemical fertilizerD. SedimentIV. Chemical factoryChoose the correct answer from the options given below : (A) A-II, B-III, C-IV, D-I(B) A-II, B-I, C-IV, D-III(C) A-I, B-IV, C-II, D-III(D) A-I, B-IV, C-III, D-II |
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Answer» Correct option is (A) A-II, B-III, C-IV, D-I
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| 21305. |
The metal complex that is diamagnetic is (Atomic number : Fe, 26; Cu, 29) (A) K3[Cu(CN)4](B) K2[Cu(CN)4](C) K3[Fe(CN)4](D) K4[FeCl6] |
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Answer» Correct option is (A) K3[Cu(CN)4] K3[Cu(CN)4] O.N. of copper is Cu+1 Cu+1 = [Ar]3d10 ⇒ Diamagnetic |
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| 21306. |
CDMA rejects (a) Narrow band interference (b) Wideband interference (c) Both A and B (d) None of the above. |
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Answer» Correct option: (a) Narrow band interference |
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| 21307. |
Consider the following reaction at certain temperature : `H_(2) (g) + Cl_(2) (g) hArr 2HCl (g)` The mixing of 1 mol of `H_(2)` with 4 moles of `Cl_(2)` from x moles of HCl at equilibrium. If we add 5 moles of `H_(2)` at equilibrium then another `2x` moles of HCl are produced. Then find `K_("eq")` for above reaction. |
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Answer» Correct Answer - 4 `{:(,H_(2) (g),+,Cl_(2) (g),hArr,2HCl (g),,),("Initially",1,,4,,-,,),("Equilibrium",1 - (x)/(2),,4 - (x)/(2),,x,,),("New Equilibrium",6 - (3x)/(2),,4 - (3x)/(2),,3x,["After adding 5 moles of" H_(2)],):}` `K_(C) = (x^(2))/((1 - (x)/(2))(4 - (x)/(2))) = ((3x)^(2))/((4 - (3x)/(2)) (6 - (3x)/(2)))` `x = 1.6` `K_(eq) = (1.6 xx 1.6)/((1 - (1.6)/(2))(4 - (1.6)/(2)))` `K_(eq) = 4` |
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| 21308. |
Total number of functional groups present in following compound : |
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Answer» Correct Answer - 5 Functional group `-overset(O)overset(||)(C)-O` (Ester) `-underset(O)underset(||)(C) -` (Ketone) `-underset(|)(N)-` (Amine) `-OH` `-underset(O)underset(||)(C)-OH` |
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| 21309. |
Find the solution of the differential equation 4y”’ + 4y” + y’ = 0. |
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Answer» The given equation in symbolic form is written as (4D3 + 4D2 + D)y = 0 and its auxiliary equation is 4D3 + 4D2 + D = 0 D(4D2 + 4D + 1) = 0 D(2D + 1)2 = 0 i.e D = 0, - 1/2, - 1/2 whence (C.F) = c1e0 + (c2x + c3)e-x/2. |
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| 21310. |
find the solution of the pair of linear equation by cross multiplication method (x+y=14)(x-Y=14) |
Answer»
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| 21311. |
Linear equations |
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Answer» The definition of a linear equation is an algebraic equation in which each term has an exponent of one and the graphing of the equation results in a straight line. An example of linear equation is y=mx + b. |
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| 21312. |
Let a set A = A = A1 ∪ A2 ∪...∪ Aki where Ai ∩ Aj = ϕ for i ≠ j 1 ≤ k. Define the relation R from A to A by R = {(x,y) : y ∈ Ai if and only if x ∈ Ai , 1 ≤ i ≤ K}. Then is(A) reflexive, symmetric but not transitive (B) reflexive, transitive but not symmetric (C) reflexive but not symmetric and transitive (D) an equivalence relation |
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Answer» (D) an equivalence relation A = {1, 2, 3} R = {(1, 1), (1, 2), (1, 3) (2, 1), (2, 2), (2, 3) (3,1), (3, 2) (3, 3)} |
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| 21313. |
An equivalence relation R in A divides it into equivalence classes A1,A2, A3. What is the value of A1 ∪ A2 ∪ A3 and A1 ∩ A2 ∩ A3 |
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Answer» A1 ∪ A2 ∪ A3 = A and A1 ∩ A2 ∩ A3 = ϕ |
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| 21314. |
Arrange carbonates fo group `2` in increasing order of thermal stability. |
| Answer» `BeCO_(3)ltMgCO_(3)ltCaCO_(3)ltSrCO_(3)ltBaCO_(3)` | |
| 21315. |
Arrange sulphates of group `2` in decreasing order of solubility of water. |
| Answer» `BeSO_(4)gtMgSO_(4)gtCaSO_(4)gtSrSO_(4)gtBaSO_(4)` | |
| 21316. |
Which of the following value of dy/dx if y = x + (1/x) |
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Answer» (A) 1 - (1/x2) |
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| 21317. |
Why disc insulators grooved at bottom? |
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Answer» To increase the creepage distance, reduce the chances of flash over. |
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| 21318. |
Acid catalysed tautomerism and base catalysed Explain the mechanism of attack using reagent D+ in acid catalysed and OD- in base catalysed (donot use bond line diagram) . What are the final ptoducts?? |
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Answer» In the acid-catalyzed reaction, the molecule is first protonated on oxygen and then loses the C-H proton in a second step. When the enol form reverts to the keto – since this is an equilibrium process – it picks up a deuteron instead of a proton since the solution is D2O. Also, the D+ (or H+ if water is the solvent) is regenerated at the end (catalyst). In the base-catalyzed reaction, the C-H proton is removed first by the base (for example hydroxide ion OH-, OD- ) and the proton (or D+ in our case) added to the oxygen atom in a second step. Also, OD- (or OH- if water is the solvent) is regenerated at the end (catalyst). The enolate ion generated from the enol (Fig. I.6) in the base-catalyzed mechanism is nucleophilic due to: Oxygen’s small atomic radius and Formal negative charge. |
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| 21319. |
In the given figure, ∠ABC and ∠ACB are complementary to each other and AD ⟂ BC. Then,(a) BD . CD = BC2 (b) AB . BC = BC2 (c) BD . CD = AD2 (d) AB . AC = AD2 |
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Answer» Correct answer is (c) BD . CD = AD2 |
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| 21320. |
The vertical columns were called ------- ? |
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Answer» the vertical were called groups in periodic table |
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| 21321. |
Find the value of k, if (3k – 2),( k+1) and 2k + 1 are in A.P |
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Answer» answer is k=1 .. |
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| 21322. |
2. For a Quadratic Equation \( a x^{2}+b x+c=0, a \neq 0 \), sum of the roots \( (\alpha+\beta) \)(a) \( \frac{c}{a} \)(b) \( \frac{-b}{a} \)(c) \( \frac{a}{b} \)(d) \( \frac{b}{a} \) |
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Answer» -b/a is your answer |
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| 21323. |
Given, S= {1,2,3,4}, state which of the following is a relation on S.a) R1= {(1,2),(2,0),(3,1)}b) R2= {(1,3),(4,2),(2,4),(1,4)}C) R3= {(1,1),(1,2),(1,3),(1,4)}d) R4= {(1,2),(0,2),(5,1),(3,2)} |
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Answer» 1) ∵ (2, 0) ∈ R1 but 0 \(\notin\) S ∴ R1 is not a relation on S 2) domain of R2 = {1, 2, 4} ⊂ S Range of R2 = {2, 3, 4} ⊂ S Thus, R2 is a relation on S. 3) domain of R3 = {1} ⊂ S Range of R3 = {1, 2, 3, 4} ⊂ S Thus, R3 is a relation on S. 4) ∵ (0, 2) ∈ R4 but 0 \(\notin\) S Thus, R4 is not a relation on S. |
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| 21324. |
Find the cartesian equation of line passing through the point having position vector \( \hat{i}-2 \hat{j}-3 \hat{k} \) and parallel to the line joining the points having position vector \( \hat{i}-\hat{j}+4 \hat{k} \) and \( 2 \hat{i}+\hat{j}+2 \hat{k} \). |
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Answer» vector equation of line joining the points having position vectors \(\vec a_1=\hat i-\hat j+4\hat k\) and \(\vec a_2=2\hat i+\hat j+2\hat k\) is \(\vec b = \vec a_2-\vec a_1=(2\hat i+\hat j+2\hat k)-(\hat i-\hat j+4\hat k)\) = \(\hat i+2\hat j-2\hat k\) Given that required line is passing through the point having position vector \(\vec a=\hat i-2\hat j-3\hat k\) \(\therefore\) Equation of required line is \((\vec r-\vec a)+\lambda \vec b=0\) (\(\because\) Required line is passing through \(\vec a\) and parallel to line \(\vec b\)) ⇒ (\(\vec r-(\hat i-2\hat j-3\hat k)\)) + \(\lambda(\hat i+2\hat j-2\hat k)=0\) which is vector equation of required line Let \(\vec r = x\hat i+y\hat j+z\hat k\) Then (x\(\hat i\) + y\(\hat j\) + z\(\hat k\)) - (\(\hat i-2\hat j-3\hat k\)) = \(-\lambda(\hat i+2\hat j-2\hat k)\) ⇒ (x - 1)\(\hat i+(y+2)\hat j+(z+3)\hat k=-\lambda\hat i-2\lambda \hat j+2\lambda\hat k\) ⇒ x - 1 = -\(\lambda\), y + 2 = -2\(\lambda\) and z + 3 = 2\(\lambda\) (On comparing coefficient of \(\hat i, \hat j\&\hat k\)) ⇒ \(\lambda\) = \(\frac{x-1}{-1}, \lambda=\frac{y+2}{-2},\lambda=\frac{z+3}{2}\) ⇒ \(\frac{x-1}{-1}=\frac{y+2}{-2}=\frac{z+3}2\) which is cartesian equation of required line Alternate method: Position vector of point is \(\hat i-2\hat j-3\hat k\) \(\therefore\) Point is (1, -2, -3) Hence, required line is passing through point (1, -2, -3) Similarly, required line is parallel to the line joining points (1, -1, 4) and (2, 1, 2). \(\therefore\) Direction ratios of line joining points (1, -1, 4) & (2, 1, 2) are \(\pm(2-1,\pm(1-(-1))),\pm(2,-4)\) or 1, 2, -2 or -1, -2, 2. \(\therefore\) Direction ratios of required line are 1,2,-2 or-1, -2, 2 and it is passing through point (1, -2, -3) \(\therefore\) Cartesian equation of required line \(\frac{x-1}1=\frac{y-(-2)}2=\frac{z-(-3)}{-2}\) or \(\frac{x-1}{-1}=\frac{y-(-2)}{-2}=\frac{2-(-3)}2\) ⇒ \(\frac{x-1}1=\frac{y+2}2=\frac{z+3}{-2}\) or \(\frac{x-1}{-1}=\frac{y+2}{-2}=\frac{z+3}2\) |
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| 21325. |
Which point defect does not change the density of `AgCl` crystals? |
| Answer» Frenkel defect, since no ions are missing from the crystal as a whole | |
| 21326. |
The equation α=(D-d)/(n-1)d is correctly matched where D=Theoretical vapour density d= Observed vapour density |
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Answer» Correct matching is equation (2) |
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| 21327. |
What other elements may be added to silicon to make electrons available for conduction of an electric current? |
| Answer» Group 15 element, e.g., phosphorous. | |
| 21328. |
A compound formed by elements \( P \) and \( Q \) crystallises in a cubic lattice where \( P \) atoms are at the corners and \( Q \) atoms are all face centres of the cube. Formula of the compound is |
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Answer» As we know, The contribution of corner atom per unit cell = 1/8. and The contribution of face centres atom per unit cell =1/2 \(\therefore\) Number of P atoms per unit cell = 8 x 1/8 \(\therefore\) Number of Q atoms per unit cell = 6 x 1/2 = 3 Therefore, the formula of compound will be PQ3. |
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| 21329. |
Write chemical equations when :(i) XeF2 is hydrolysed.(ii) PtF6 and Xenon are mixed together. |
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Answer» [Hint : (i) 2XeF2 (s) + 2H2O (l) → 2Xe (g) + 4HF (aq + O2 (g) |
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| 21330. |
Write IUPAC name of O2 +[PtF6]. |
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Answer» [Hint : Dioxygenyl hexafluoroplatinate(iv).] |
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| 21331. |
(i) Hydrolysis of XeF6 is not regarded as a redox reaction. Why ?(ii) Write a chemical equation to represent the oxidizing nature of XeF4. |
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Answer» (i) Because oxidation number of Xe do not change during hydrolysis of XeF6. |
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| 21332. |
Suggest reason why only known binary compounds of noble gases are fluorides and oxides of Xenon and to a lesse extent of Kryton. |
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Answer» [Hint : F and O are most electronegative elements Kr and Xe both have low ionization enthalpies as compared to He and Ne.] |
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| 21333. |
The formation of O2 +[PtF6]– is the basis for the formation of xenon fluorides. This is because(a) O2 and Xe have comparable sizes(b) both O2 and Xe are gases(c) O2 and Xe have comparable ionisation energies(d) Both (a) and (c) |
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Answer» (i) The first ionization energy of xenon (1, 170 kJ mol– 1 ) is quite close to that of dioxygen (1,180 kJ mol–1). (ii) The molecular diameters of xenon and dioxygen are almost identical. Based on the above similarities Barlett (who prepared O2 + [PtF6 ] – compound) suggested that since oxygen combines with PtF6 , so xenon should also form similar compound with PtF6 . |
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| 21334. |
Molar volume of an Ideal gas is `0.45 dm^(3)//mol`. The molar volume of air (assumming as real gas) under the same condition is `0.9dm^(3)//mol`. The point which corresponds to air the given graph is : A. `B`B. `D`C. `A`D. None of these |
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Answer» Correct Answer - B Molar volume of an ………. `z = (0.9)/(0.45) =2` , `zgt1` |
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| 21335. |
Predict the shape and the asked angle (90º or more or less) in the following case :XeF2 and the angle F Xe F |
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Answer» [Hint : Linear, 180º] |
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| 21336. |
Why is N2 less reactive at room temperature? |
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Answer» The two N atoms in N2 are bonded to each other by very strong triple covalent bonds. The bond dissociation energy of this bond is very high. As a result, N2 is less reactive at room temperature. |
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| 21337. |
Write the chemical equation involved in the preparation of XeF4. |
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Answer» [Hint : Xe (g) + 2F2 (g) → XeF4 (s)] |
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| 21338. |
Why is ICl more reactive than I2? |
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Answer» ICl is more reactive than I2 because I−Cl bond in ICl is weaker than I−I bond in I2. |
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| 21339. |
Balance the following equation: XeF6 + H2O → XeO2F2 + HF |
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Answer» Balanced equation |
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| 21340. |
The electron gain enthalpy with negative sign for oxygen (- 141 KJ mol-1) is numerically less than that for sulphur (- 200 KJ mol-1). Give reason. |
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Answer» [Hint : Due to smaller size of oxygen than sulphur electron-electron repulsion is more in oxygen than sulphur.] |
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| 21341. |
H2O is a liquid while inspite of a higher molecular mass, H2S is a gas. Explain. |
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Answer» [Hint : H2O molecules are stabilized by intermolecular hydrogen bonding, while H2S by weak van der Waals forces.] |
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| 21342. |
Large heat transfer coefficients for vapour condensation can be achieved by promoting (a) Film condensation (b) Dropwise condensation (c) Cloud condensation (d) Dew condensation |
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Answer» (b) Dropwise condensation (b) Since dropwise condensation offers lesser thermal resistance during phase change thus can enhance heat transfer rate between vapour and solid surface. |
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| 21343. |
Which one of the following valves is provided for starting the engine manually, during cold weather conditions? (a) Starting jet valve (b) Compensating jet valve (c) Choke valve (d) Auxiliary air valve |
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Answer» (c) Choke valve |
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| 21344. |
Artificial satellites go round the earth in their respective orbits. Astronauts are able to float in side the satellite. Inside space of the satellite could be treated as gravity free space. If a beaker filled with a liquid upto height h having a small hole in the bottom is placed in such a satellite, you will wonder te liquid does not come out of the hole. You have to squeeze or force the liquid to come out. suppose a constant pressure p is applied on the liquid through piston to force it out through the hole. Out side pressure could be neglected in comparison with `p` Cross-sectional area of beaker is too greater than that of hole `(Agtgta)`A. Velocity with which liquid comes out of the hole is `sqrt(p/(rho))`B. Velocity with which liquid comes out of the is `(Ah)/asqrt((2p)/(rho))`C. Time taken to empty the beaker is `(Ah)/a sqrt((rho)/(2p))`D. Time taken to empty the beaker is `(Ah)/a sqrt((2p)/(rho))` |
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Answer» Correct Answer - B::C `p=1/2pV^(2)impliesV=sqrt((2p)/(rho))` `t=(Ah)/(a.v)=(Ah)/(a.sqrt((2p)/(rho)))` |
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| 21345. |
The displacement-time graph of a moving particle with constant acceleration is shown in. The velocity-time is given by .A. B. C. D. |
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Answer» Correct Answer - A `From big :- For time interval `t=0` to `t=1sec` slope of x-t graph os negative and increasing so velocity increases in negative direction ` For t=1 to 2sec` The slope is +ve and decreasing so velocity is decreasing in + ve direction and become zero at so (A) is correct |
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| 21346. |
A bird flies for 4 seconds with a velocity of `|t-2|m//sec.` In a straight line, where `t=` time in seconds. It covers a distance ofA. 2mB. 4mC. 6mD. 8m |
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Answer» Correct Answer - B `Here V=|t-2|=2-t fortle2 Rightarrowt-2for4getge2` ` V=(dx)/dtor underset0oversetx intdx =underset0oversetx intVdt` `underset0overset2 int (2-t)dt+ underset2overset4 int (t-2)dt=4meterAns` |
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| 21347. |
They are people of yellow complexion, oblique eyes, high chick bones, spare hair and medium height," The reference here is to (a) Nordic Aryans (b) Austrics (c) Negroids (d) Mongoloids |
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Answer» They are people of yellow complexion, oblique eyes, high chick bones, spare hair and medium height," The reference here is to Mongoloids. |
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| 21348. |
A projectile is to be projected towards enemy territory at the same horizontal level. The initial velocity of the projectile is known to be `100 pm 1 m//s` Initial angle of the projectile is known to be projected `45^(@) pm 1^(@)` What is the possible range of the projectile?A. `990mleRle 1010m`B. `980mleRle1020m`C. `970mleRle1030m`D. `930mleRle970m` |
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Answer» Correct Answer - B `R=(u^(2)sin20)/g=(100^(2)xx1)/10=1000m` `(DeltaR)/R=(2Deltau)/u+(cos20)/sin20xxDeltatheta` `(DeltaR)/1000=(2xx1)/100rightarrowDeltaR=20m` `980mleRleR1020m]` |
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| 21349. |
The acceleration of a particle is given by `vec(a) = [2hat(i)+6that(j)+(2pi^(2))/(9) "cos" (pit)/3hat(k)]ms^(-2)` At `t=0 ,vec(r)=0 and vec(v) =(2hat(i)+hat(j))ms^(-1)` The position vector at `t=2` s isA. `(8hat(i)+10hat(j)+hat(k))m`B. `(8hat(i)+10hat(j)+3hat(k))` mC. `(3hat(i)+8hat(j)+10hat(k))m`D. `(10hat(i)+3hat(j)+8hat(k))m` |
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Answer» Correct Answer - B `vec(a)=[2hat(i)+6that(j)+(2pi^(2))/9 cos ((pit)/3) hat(k)] m//s^(2)` at `t=0, vec(r)=0` and `vec(v)=(2hat(i)+hat(j)) m//s` The position vector at `t=2` sec is `(dvec(v))/(dt)=[2hat(i)+6that(j)+(2pi^(2))/9 "cos" ((pit)/3) hat(k)]` `underset(2hat(i)+hat(j)) oversetvec(v)int dvec(v)=underset0overset t int (2hat(i)+6that(j)+(2pi^(2))/9 "cos"((pit)/3)hat(k))dt` `vec(v)-(2hat(i)+hat(j))=2that(i)+3t^(2)hat(j)+(2pi^(2))/9xx3/pi "sin" (pi/3)t hat(k)` `vec(v)=(2hat(i)+hat(j))+2that(i)+3t^(2)hat(j)+2/3 pi "sin"(pi/3)that(k)` `vec(v)=[(2+2t)hat(i)+(3t^(2)+1)hat(j)+(2pi)/3 "sin" (pi/3t)hat(k)]` `vec(v)=(dvec(r))/(dt)=[(2+2t)hat(i)+(3t^(2)+1)hat(j)+(2pi)/3 "sin" (pi/3t)hat(k)]` `underset0 oversetvec(r) int dvec(r)=underset0overset t int [(2+2t)hat(i)+(3t^(2)+1)hat(j)+((2pi)/3 sin(pi/3t)hat(k))dt` `vec(r)=(2t+t^(2))hat(i)+(t^(3)+t)hat(j)+(2pi)/3xx(-cos(pit//3))/(pi//3)hat(k)` `vec(r)=(2t+t^(2))hat(i)+(t^(3)+t)hat(j)-2"cos" (pit)/3 hat(k)` `vec(r)=(2xx2+4)hat(i)+(8+2)hat(j)-2[cos((2pi)/3)-1]hat(k)` `vec(r)=8hat(i)+10 hat(j)+3 hat(k)` |
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| 21350. |
In an optical bench experiment to measure the focal length of a concave mirror random error in focal length will beA. minimum when `u = f` and maximum when `u= infty`B. minimum when `u = infty` and minimum when `u = f`C. minimum when `u= 0` and maximum when `u= 2f`D. minimum when `u = 2f` and maximum when `u =0` |
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Answer» Correct Answer - D `(Deltaf)/f^(2)=(Deltau)/u^(2)+(Deltav)/v^(2) Deltau=Deltav` for optical bench ` Rightarrow 1/(f^(2))xxd(Deltaf)=Deltau[-2/u^(3)-2/v^(3)xx(dv)/(du)]_(for min error)=0` ` (dv)/(du)=-v^(3)/u^(3)=-v^(2)/u^(2)Rightarrow v=u` ` for `u = 2f`, error is min |
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