Explore topic-wise InterviewSolutions in Current Affairs.

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.

How many moles of acetic anhydride `(Ac_(2)O)` is needed to react completely with tataric acid, ribose and glucose respectively, A. 2,4,5B. 2,3,4C. 4,5,6D. 4,5,5

Answer» Correct Answer - A
Depends upon number of -OH group for the formation of ester by acylation.
2.

The IUPAC name of the complex[Pt(NH3)2Cl(NH2CH3)]Cl is : (1) Diammine (methanamine) chlorido platinum (II) chloride (2) Bisammine (methanamine) chlorido platinum (II) chloride (3) Diamminechlorido (aminomethane) platinum(II) chloride (4) Diamminechlorido (methanamine) platinum (II) chloride

Answer»

Answer is (4)

IUPAC name

[Pt(NH3)2Cl(NH2CH3)]Cl -Diamminechlorido (methanamine) platinum(II)chloride.

Answer is (4) Diamminechlorido (methanamine) platinum (II) chloride

3.

Oxidation number of potassium in K2O, K2O2 and KO2, respectively, is : (1) +1, +4 and +2 (2) +1, +2 and +4 (3) +1, +1 and +1 (4) +2 , +1 and + 1/2

Answer»

Answer is (3) +1, +1 and +1

Potasisum has an oxidation of +1 (only) in combined state.

Answer is (3)

Oxidation number of K in K2O, K2O2 and KO2 = +1, +1, +1

4.

All of the following statements about bacterial promoters are true except (A) They are smaller than eukaryotic promoters (B) They have two consensus sequences upstream from the transcription star site (C) TATA box is the site for attachment of RNA polymerase (D) TATA box has a high melting temperature

Answer»

(D) TATA box has a high melting temperature

5.

Energy released during movement of electrons through the photosystems in photosynthesis is used to drive protons across the membrane against concentration gradient. As a result the protons accumulate inA. thylakoid lumenB. stoma of chloroplastC. matrix of mitochondrionD. none of these

Answer» Correct Answer - A
6.

Add a constraint in table empl that declares column grade

Answer»
ALTER TABLE students ADD CONSTRAINT NN_Grade CHECK (adm_no IS NOT NULL);
7.

Interferon (A) Is virus specific (B) Is a bacterial product (C) Is a synthetic antiviral agent (D) Requires expression of cellular genes

Answer»

(D) Requires expression of cellular genes

8.

Repressor binds to DNA sequence and regulate the transcription. This sequence is called (A) Attenuator (B) Terminator (C) Anti terminator (D) Operator 

Answer»

(D) Operator 

9.

The function of a repressor protein in an operon system is to prevent synthesis by binding to(A) The ribosome(B) A specific region of the operon preventing transcription of structural genes(C) The RNA polymerase(D) A specific region of the mRNA preventing translation to protein

Answer»

(B) A specific region of the operon preventing transcription of structural genes 

10.

Which one of the following reactions indicates the reducing ability of hydrogen peroxide in basic medium ?(A) HOCI + H2O2 → H3O++ CI- + O2(B) PbS + 4H2O2 → PbSO4 + 4H2O(C) 2MnO-4, +3H2O2, → 2MnO2, +302, +2H2O + 2OH- (D) PbS + 4H2O2 → PbSO4 + 3H2O

Answer»

(C) 2MnO-4, +3H2O2, → 2MnO2, +302, +2H2O + 2OH- 

In option (A) and (C) reducing action of hydrogen peroxide is shown. 

In option (A) it is in acidic medium, in option (B) it is in basic medium. 

or 

For reducing ability H2O2 changes to O2 , i.e. oxidize , so in option 'A' & 'C' O2 is formed but 'A' is in acidic medium so option - C correct.

11.

What are the three main types of RNA? What is meant by heterogeneous RNA?

Answer»

Messenger RNA, or mRNA, transfer RNA, or tRNA, and ribosomal RNA, or rRNA, are the three main types of RNA.

The newly formed RNA molecule, a precursor of mRNA, is called heterogeneous RNA (hnRNA). The heterogenous RNA bears portions called introns and portions called exons. The hnRNA is processed in many chemical steps, introns are removed and mRNA is created formed only of exons, the biologically active nucleotide sequences.

12.

Initiation of protein synthesis requires (A) ATP (B) AMP (C) GDP (D) GTP

Answer»

Correct option (D) GTP

13.

In isolation of which one of the following metals from their ores, the use of cyanide salt is not commonly involved ? (A) Zinc (B) Gold (C) Silver (D) Copper

Answer»

Correct option is (D) Copper

For ZnS, KCN is used as depressant. 

For Gold and silver ⇒ leaching [Cyanide process]

14.

During ovulation which hormone secretion increases a. L.H b. F. S. H.c. L.H and F.S. H. both d. high L. H. and low F. S. H.

Answer»

Answer: C. L.H and F.S. H. both 

15.

Where can RNA be found within cells?

Answer»

In the eukaryote cell nucleus RNA can be found dispersed in the nuclear fluid, along with DNA, and as the main constituent of the nucleolus. In cytosol (in eukaryotes or in bacteria) RNA molecules can be found free, as structural constituent of ribosomes (organelles specialized in protein synthesis) or even associated with them in the process of making proteins.

In replication the enzyme DNA polymerase catalyzes the formation of a new polynucleotide chain using free nucleotides in solution and putting them in the new chain according to the DNA template exposed and to the rule A-T, C-G. In transcription the enzyme RNA polymerase makes a new polynucleotides chain according to the DNA template exposed obeying, however, the rule AU, C-G.

In replication the original template DNA a chain is kept bound by hydrogen bonds to the newly formed DNA chain and a new DNA molecule is then created. In transcription the association between the template DNA chain and the newly formed RNA is undone and RNA constituted of only one polynucleotide a chain is liberated.

16.

The electronic configuration of Pt (atomic number 78) is:(A) [Xe] 4f14 5d9 6s1 (B) [Kr] 4f14 5d10 (C) [Xe] 4f14 5d10 (D) [Xe] 4f14 5d8 6s2

Answer»

Correct option is (A) [Xe] 4f14 5d9 6s1 

78Pt = [Xe] 4f14 5d9 6s1 (Exceptional electronic configuration)

17.

The best method for drying a cloth is-(a) Sun shine and air(b) Drier (c) Iron (d) Heater

Answer»

The best method for drying a cloth is Sun shine and air.

18.

Arrange the following in the decreasing order of their covalent character :(A) LiCl (B) NaCl(C) KCl(D) CsCIQuestion: Choose the most appropriate answer from the options given below :(A) (A) > (C) > (B)> (D) (B) (B) > (A) > (C) > (D) (C) (A) > (B) > (C) > (D) (D) (A) > (B) > (D) > (C)

Answer»

Correct option is (C) (A) > (B) > (C) > (D) 

19.

Which of the following is a correct statement ? (A) Brownian motion destabilises sols. (B) Any amount of dispersed phase can be added to emulsion without destabilising it. (C) Mixing two oppositely charged sols in equal amount neutralises charges and stabilises colloids. (D) Presence of equal and similar charges on colloidal particles provides stability to the colloidal solution.

Answer»

(D) Presence of equal and similar charges on colloidal particles provides stability to the colloidal solution.

As equal & similar charge particle will repel each other, hence will never precipitate.

20.

The solubility of AgCl will be maximum in which of the following ? (A) 0.01 M KCl (B) 0.01 M HCI (C) 0.01 M AgNO3 (D) Deionised water

Answer»

(D) Deionised water

In deionized water no common ion effect will take place so maximum solubility

21.

Which of the following are isoclectronic?(a) HF and H2O(b) CH4 and SF6(c) O2 and 03(d) H2 and F2

Answer»

(a) HF and H2O

HF = 1 + 9 = 10

H2O = 2 + 8 = 10

22.

Define Zygote

Answer»
A Zyhote is the first diploid cell that is formed by the fusion of male and female gametes resulting in the formation of an embryo 
23.

A mirror forms an image which is 30 cm from an object and twice its height.(a) Where must the mirror be situated?(b) What is the radius of curvature?(c) Is the mirror convex or concave?

Answer»

Let the image formed is virtual and erect.

V – u = 30 cm

m = 2

(a) m = - (v/u)

2 = - (v/u)

V = -2u

-2u – u = 30 cm

u = -10 cm

(b) v = -2u = 20 cm

1/v + 1/u = 1/f

1/20 + 1/-10 = 1/f

1/f = -1/20

f = -20 cm

R = 2f = -40 cm

 Concave mirror

24.

Some people take large amounts of vitamins and minerals over periods of years. _____ There is no evidence to support their view. In fact a recent study says that people who take vitamin supplements are not any healthier for it and do not live longer. A) Children suffer more from vitamin deficiencies than adults do. B) Our bodies use vitamins in tiny amounts to build and repair tissues. C) Exercise and no smoking are essential for good health. D) They assume that if a little is good for them a lot must be better. E) To work out your own nutritional needs, it's best to consult a doctor.

Answer»

Correct option is D) They assume that if a little is good for them a lot must be better

25.

Magnetic Susceptibility in Vacuum is - (A) 0 (B) 1 (C) ∞ (infinity) (D) 100

Answer»

Correct answer is (A)

26.

The speed of electromagnetic wave in vacuum is -(A) \(C = \frac{1}{\sqrt{\mu_0 \in_0}}\)(B) \(C = \sqrt{\frac{\in_0}{\mu_0}}\)(C) \(C = \frac{1}{\sqrt{\in_0}}\)(D) \(C = \frac{1}{\sqrt{\mu_0}}\)

Answer»

Correct answer is (A) \(C = \frac{1}{\sqrt{\mu_0 \in_0}}\)

27.

The value of Wave-length of X-rays is -(A) about 10-7 m (B) about 107 m (C) about 107 mm (D) 1 cm

Answer»

Correct answer is (A) about 10-7

28.

How does the width of a depletion region of a pn junction vary if doping concentration is increased?

Answer»

With increase in the rate of doping, width of depletion region generated at the junction decreases.

The answer is: Decreases

29.

The direction of propagation of electromagnetic wave is -(A) Parallel to \(\vec{E}\)(B) Parallel to \(\vec{B}\)(C) Parallel to \(\vec{B}\) x \(\vec{E}\)(D) Parallel to \(\vec{E}\) x \(\vec{B}\)

Answer»

Correct answer is (C) Parallel to \(\vec{B}\) x \(\vec{E}\)

30.

In half wave rectification, what is the output frequency if input frequency is 25 Hz.

Answer»

Input frequency = 25 Hz

for a half wave rectification, the output frequency is equal to its frequency.

\(\therefore\) Output frequency = 25 Hz

The answer is : 25Hz

31.

Which specially fabricated pn junction diode is used for detecting light intensity?

Answer»

A p-n junction with reverse bias can be used as a photo-diode to measure light intensity.

The answer is : Photodiode

32.

The value of charge of an electron is -(A) 1.6 x 10-21 C (B) 1.6 x 10-19 C (C) 1.6 x 10-9 C (D) 1.6 x 10-11 C

Answer»

Correct answer is (B) 1.6 x 10-19 C

33.

Which of the following is correct ?(A) 1 ev = 1.6 x 10-19 J (B) 1 ev = 10-19 J (C) 1 ev = 1.6 x 1019 J (D) 1 ev = 1019 J

Answer»

Correct answer is (A) 1 ev = 1.6 x 10-19 J

34.

Dimension of Planck Constant is(A) ML2T-1 (B) ML2T2(C) MLT-1 (D) MLT-2

Answer»

Correct answer is (A) ML2T-1

35.

When a voltage drop across a pn junction diode is increased from 0.70 V to 0.71V, the change in the diode current is 10 mA .What is the dynamic resistance of diode?

Answer»

For a p-n junction diode, the dynamic resistance is given by:

r = \(\frac{\Delta V}{\Delta I}\)

Given that:

ΔV = 0.71 - 0.70 = 0.01 V = 10-2 V

ΔI = 10-3 x 10 A = 10-2 A

\(\therefore\) r = \(\frac{10^{-2}}{10^{-2}}\) = 1 Ω.

Dynamic resistance =change in voltage/change in current=1 ohm.

36.

The dimension of `L//C` is equivalent to that of (`L to` inductance, `C to`capacitance)A. `omega^(2)`, `omega-=`angular frequency.B. `L^(2)`, `L-=`inductanceC. `R^(2)`, `R-=` resistance.D. none of these

Answer» `L//R="time"`, `CR=`time
37.

A radioactive sample undergoes decay as per the following gragp. At time` t=0`, the number of undecayed nuclei is `N_(0)`. Calculate the number of nuclei left after `1 h`. .A. `N_(0)//e^(8)`B. `N_(0)//e^(10)`C. `N_(0)//e^(12)`D. `N_(0)//e^(14)`

Answer» `A=A_(0)e^(-lambda t)`
38.

In the circuit shown in figure, when the input voltage of the base resistance is 10 V, `V_(be)` is zero and `V_(ce)` is also zero. Then A. 133B. 1330C. 13.3D. 1.33

Answer» Correct Answer - A
`I_(B)=(V_(i))/(R_(B))=(10V)/(400xx10^(3)Omega)=25muA`
`I_(C)=(10V)/(3kOMega)=3.33mAimplies beta=(I_(C))/(I_(B))=(3.33xx10^(-3))/(25xx10^(-6))=133`
39.

When a point source of light is at a distnace of 1 m from a photo cell, the cut off voltage is is found to be V. if the same source is placed at 3m distance from photo cell, the cut of voltage will beA. VB. `(V)/(2)`C. `V/4`D. `V/sqrt(2)`

Answer» Correct Answer - A
By changing distance of source, photoelectric current charges. But there is not change in stopping potential.
40.

A radioactive sample undergoes decay as per the following gragp. At time` t=0`, the number of undecayed nuclei is `N_(0)`. Calculate the number of nuclei left after `1 h`. .A. `(N_(0))/(e^(8))`B. `(N_(0))/(e^(10))`C. `(N_(0))/(n^(12))`D. `(N_(0))/(e^(14))`

Answer» Correct Answer - C
`t=0,N=N_(0)`
t=6.93 min, `N=(N_(0))/(4)`
`N_(0)/4` is the sample left after two half lives.
`2T_(1//2)=6.93` or `T_(1//2)=(6.93)/(2)` min
`lamda=(0.693)/(T_(1//2))=0.2"minute"^(-1)`
at time t=1h=60 minute
`N=N_(0)e^(-lamdat)=N_(0)e^(-0.2xx60)=(N_(0))/(e^(12))`
41.

A nuclear reaction along with the masses of the particle taking part in it is as follows `underset("1.002 amu")(A)+underset("1.004 amu")(B) to underset("1.001 amu")(C)+underset("1.003 amu")(D)+QMeV` the energy Q is liberated in the reaction isA. 1.234 MeVB. 0.931 MeVC. 0.465 MeVD. 1.862 MeV

Answer» Correct Answer - D
`Q=(1.002+1.004-1.001-1.003)(931.5)MeV`
`=1.863MeV`
42.

(v) \( \int_{0}^{\frac{\pi}{2}} \sin ^{2} x \cos ^{4} x d x \)

Answer»

\(\int_0^{\frac{\pi}{2}} sin^2x\,cos^4x\,dx\)

\(\frac{\Gamma(\frac{2+1}{2})\Gamma(\frac{4+1}{2})}{2\Gamma{(\frac{2+4+2}{2})}}\)

(∵ \(\int_0^{\frac{\pi}{2}} sin^m\theta\,cos^n\theta\,d\theta\) = \(\frac{\Gamma(\frac{m+1}{2})\Gamma(\frac{n+1}{2})}{2\Gamma{(\frac{m+n+2}{2})}}\))

\(\frac{\Gamma(\frac{3}{2})\Gamma(\frac{5}{2})}{2\Gamma{(4)}}\)

\(\frac{\frac{1}{2}\Gamma(\frac{1}{2})\times \frac{3}{2}\times \frac{1}{2}\Gamma(\frac{1}{2})}{2\times 3!}\)

(∵ \(\Gamma(n+1)\) = n\(\Gamma\)(n),n>0 & \(\Gamma\)(n+1) = n!, n∈N)

\(\frac{3}{8}\) x \(\frac{\sqrt{\pi}\times {\sqrt\pi}}{2\times 6}\) 

\(\frac{\pi}{32}\).

Hence,

\(\int_0^{\frac{\pi}{2}} sin^2x\,cos^4x\,dx\) = \(\frac{\pi}{32}\).

43.

(vii) \( \int_{0}^{\frac{\pi}{2}} \sin ^{3} \theta \cos ^{5} \theta d \theta \)

Answer»

\(\int_0^\frac{\pi}{2} sin^3\theta\,cos^5\theta\,{d}\theta\)

\(\frac{\Gamma(\frac{3+1}{2})\Gamma(\frac{5+1}{2})}{2\Gamma(\frac{3+5+2}{2})}\) 

\(\frac{\Gamma(2)\Gamma(3)}{2\Gamma(5)}\)

\(\frac{1!2!}{2\times 4!}\)

(∵ \(\Gamma\)(n+1) = n!, n ∈ N)

\(\frac{1}{24}\)

Hence,

\(\int_0^\frac{\pi}{2} sin^3\theta\,cos^5\theta\,{d}\theta\) = \(\frac{1}{24}\) 

44.

(vi) \( \int_{0}^{2 \pi} \sin ^{7} \frac{x}{4} d x \)

Answer»

Let I = \(\int_0^{2\pi}sin^7\frac{x}{4}{d}x\)

\(\int_0^{2\pi}(sin^2\frac{x}{4})^3sin\frac{x}{4}{d}x\)

\(\int_0^{2\pi}(1-cos^2\frac{x}{4})^3sin\frac{x}{4}{d}x\) 

Let cos\(\frac{x}{4}\) = t

⇒ \(-\frac{1}{4}\) sin\(\frac{x}{4}\) dx = dt

⇒ sin\(\frac{x}{4}\)dx = -4dt

Limits changes to t = cos 0 = 1 to t =  cos\(\frac{2\pi}{4}\) 

= cos\(\frac{\pi}{2}\) = 0

∴ I = \(\int_1^0 \) (1-t2) x -4dt

= 4\(\int_0^1 \)(1-t2)3 dt

= 4\(\int_0^1 \)(1-3t2+3t4-t6)dt

= 4 [t - 3\(\frac{t^3}{3}\)+ 3\(\frac{t^5}{5}\) - \(\frac{t^7}{7}\)\(]^1_0\) 

= 4(1-1+\(\frac{3}{5}\)\(\frac{1}{7}\))

= 4 x \(\frac{21-5}{35}\) 

\(\frac{64}{35}\).

45.

The impedance of a series LCR circuit is -(a) R + XL + XC(b) \(\sqrt{\frac{1}{X^2_C}+\frac{1}{X^2_L}+R^2}\) (c) \(\sqrt{X^2_L-X^2_C+R^2}\) (d) \(\sqrt{R^2+(X_L-X_C)^2}\)

Answer»

Option : (d) \(\sqrt{R^2+(X_L-X_C)^2}\)

46.

When an alternating voltage E = Eosin ωt is applied to circuit, a current I = Iosin (ωt+π/2) flows through it. The average power dissipated in the circuit is :(a) Erms.Irms(b) EoIo(c) \(\frac{E_oI_o}{\sqrt2}\) (d) Zero

Answer»

Option : (d) Zero

47.

(vi) \( f(x)=\log _{10}\left(1-\log _{7}\left(x^{2}-5 x+13\right)\right)+\cos ^{-1}\left(\frac{3}{2+\sin \frac{9 \pi x}{2}}\right) \)

Answer» Question is incorrect. Don't know what, we have to find?
48.

A current carrying wire kept in a uniform magnetic field,will experience a maximum force when it is :(a) perpendicular to the magnetic field(b) parallel to the magnetic field(c) at an angle of 45° to the magnetic field(d) at an angle of 60° to the magnetic field

Answer»

Option : (a) perpendicular to the magnetic field

49.

I.` x^(2) - 36x+324 = 0" "II.3y^(2)+17y+24 = 0`A. if`x lt y`B. if`x le y`C. if`x gt y`D. if`x ge y`

Answer» Correct Answer - C
I. ` x^(2) - 36x + 324 = 0`
` x^(2) -2 xx 18 xx x + (18)^(2) = 0`
` (x - 18)^(2) = 0`
` x = 18`
II. ` 3y^(2) + 17y + 24 = 0`
` 3y^(2) + 9y + 8y + 24 = 0`
` 3y(y+3) + 8 (y + 3) = 0`
` (y+3)(3y+8) = 0`
` y =- 3, - 8/3`
` x gt y`
50.

`(x-4)(x-3)=(x-6)(x-5)`` (y-9)(y-3)= (y-4)(y-3)`A. ` x gt y` B. ` x lt y`C. ` x ge y`D. ` x le y`

Answer» Correct Answer - A
`(x-4)(x-3)=(x-6)(x-5)`
` 4x = 18`
` x = 4.5`

` (y-9)(y-3)=(y-4)(y-3)`
y =3