From the wave equation y=0.5 sin[(2π/3.2)(64t−x)], what is the frequency of the wave?
उत्तर देखें
सही उत्तर: (C) 20 Hz
1 अंक · 2023 · सेट A
प्रश्न 52
Identify which expression is not Maxwell’s equation for time-varying fields.
उत्तर देखें
सही उत्तर: (A) ∇·J + ∂ρ/∂t = 0
1 अंक · 2023 · सेट A
प्रश्न 53
The voltage induced across a stationary conductor in an external static magnetic field
उत्तर देखें
सही उत्तर: (C) Is zero
1 अंक · 2023 · सेट A
प्रश्न 54
A wire in the shape of an equilateral triangle with sides of length 1 m sits in a magnetic field of 2 T pointing to the right. What is the magnitude of the magnetic flux through the triangle?
उत्तर देखें
सही उत्तर: (A) 0 Wb
1 अंक · 2023 · सेट A
प्रश्न 55
Which statement(s) is/are true regarding Biot–Savart law? (i) Magnetic field is directly proportional to the length of the element. (ii) Biot–Savart law deals with electric field. (iii) Magnetic field is directly proportional to current through the conductor. Select the correct answer.
उत्तर देखें
सही उत्तर: (C) (i) and (iii)
1 अंक · 2023 · सेट A
प्रश्न 56
Find the value of current i in the given circuit (as shown in the printed diagram).
उत्तर देखें
सही उत्तर: (C) 1 A
1 अंक · 2023 · सेट A
प्रश्न 57
Which statement is not correct about the quality factor of a parallel resonance circuit?
उत्तर देखें
सही उत्तर: (D) More than one of the above
1 अंक · 2023 · सेट A
प्रश्न 58
In a photoelectric experiment, sodium (work function 2.3 eV) and tungsten (work function 4.5 eV) are illuminated by ultraviolet light of the same wavelength. If tungsten’s stopping potential is 1.8 V, what is sodium’s stopping potential?
उत्तर देखें
सही उत्तर: (A) 4 V
1 अंक · 2023 · सेट A
प्रश्न 59
The fine structure of atomic spectral lines arises from
उत्तर देखें
सही उत्तर: (A) Electron spin–orbit coupling
1 अंक · 2023 · सेट A
प्रश्न 60
An atom with proton number 84 and nucleon number 216 decays by emitting an alpha particle. What is the structure of the new nucleus?
उत्तर देखें
सही उत्तर: (A) Proton number 82, nucleon number 212
1 अंक · 2023 · सेट A
प्रश्न 61
Which of the following reactions is not allowed?
उत्तर देखें
सही उत्तर: (B) Λ⁺ + n → Σ⁺ + p
1 अंक · 2023 · सेट A
प्रश्न 62
Donor-type impurities are materials of which group of the periodic table?
उत्तर देखें
सही उत्तर: (A) Group V
1 अंक · 2023 · सेट A
प्रश्न 63
In an n-type semiconductor, the Fermi level lies
उत्तर देखें
सही उत्तर: (B) Below the bottom of the conduction band
1 अंक · 2023 · सेट A
प्रश्न 64
The maximum efficiency of a half-wave rectifier is
उत्तर देखें
सही उत्तर: (B) 40.6%
1 अंक · 2023 · सेट A
प्रश्न 65
Consider: (i) amplitude modulation, (ii) frequency modulation, (iii) phase modulation, (iv) pulse modulation. Which are used for telecasting TV programmes?
उत्तर देखें
सही उत्तर: (C) (i) and (ii)
1 अंक · 2023 · सेट A
प्रश्न 66
For every 10°C increase in temperature, the reverse saturation current of a p–n junction increases by
उत्तर देखें
सही उत्तर: (B) 2 times
1 अंक · 2023 · सेट A
प्रश्न 67
The band-gap energies of silicon and germanium photodiodes are 1.1 eV and 0.67 eV respectively. What are their respective cutoff wavelengths?
उत्तर देखें
सही उत्तर: (A) 1127.27 nm, 1850.75 nm
1 अंक · 2023 · सेट A
प्रश्न 68
Which method can produce a high degree of homogeneity in the creation of ZnFe₂O₄ spinel?
उत्तर देखें
सही उत्तर: (C) Coprecipitation method
1 अंक · 2023 · सेट A
प्रश्न 69
_____ is a crystalline solid’s basic repetitive structural unit.
उत्तर देखें
सही उत्तर: (C) Unit cell
1 अंक · 2023 · सेट A
प्रश्न 70
For all the reactions, what is the nature of chemical dissociation?
उत्तर देखें
सही उत्तर: (D) More than one of the above
1 अंक · 2023 · सेट A
प्रश्न 71
The radius of an atomic nucleus is of the order of
उत्तर देखें
सही उत्तर: (B) 10⁻¹³ cm
1 अंक · 2023 · सेट A
प्रश्न 72
An atomic orbital is
उत्तर देखें
सही उत्तर: (C) The region in which there is a maximum probability of finding an electron
1 अंक · 2023 · सेट A
प्रश्न 73
In the rate equation, when the concentration of the reactants is unity, the rate is equal to the
उत्तर देखें
सही उत्तर: (A) Specific rate constant
1 अंक · 2023 · सेट A
प्रश्न 74
In the reaction 2A + B → A₂B, if the concentration of A is doubled and that of B is halved, how will the reaction rate change?
उत्तर देखें
सही उत्तर: (A) Increase 2 times
1 अंक · 2023 · सेट A
प्रश्न 75
Substance A decomposes by a first-order reaction, starting with [A]=2.00 M. After 200 minutes, [A]=0.15 M. What is t₁/₂?
उत्तर देखें
सही उत्तर: (A) 53.72 minutes
1 अंक · 2023 · सेट A
प्रश्न 76
Which assertion about the main cell is correct?
उत्तर देखें
सही उत्तर: (A) A mercury cell is an example of a primary cell.
1 अंक · 2023 · सेट A
प्रश्न 77
Which of the following does a catalyst alter in a chemical reaction?
उत्तर देखें
सही उत्तर: (B) Activation energy
1 अंक · 2023 · सेट A
प्रश्न 78
Photochemistry deals with the study of
उत्तर देखें
सही उत्तर: (C) Reactions that proceed with absorption of visible or ultraviolet light
1 अंक · 2023 · सेट A
प्रश्न 79
The number of photons passing through a unit area in a unit time is called
उत्तर देखें
सही उत्तर: (C) Intensity of light
1 अंक · 2023 · सेट A
प्रश्न 80
The transition without radiation emission of a molecule from a stable excited state to an unstable excited state, leading to dissociation, is called
उत्तर देखें
सही उत्तर: (A) Predissociation
1 अंक · 2023 · सेट A
प्रश्न 81
Which products are obtained when Na₂CO₃ is added to a copper sulphate solution?
उत्तर देखें
सही उत्तर: (A) Basic copper carbonate, sodium sulphate and CO₂
1 अंक · 2023 · सेट A
प्रश्न 82
Which pair has similar atomic radii?
उत्तर देखें
सही उत्तर: (B) Mo and W
1 अंक · 2023 · सेट A
प्रश्न 83
According to IUPAC nomenclature, sodium nitroprusside dihydrate is named
उत्तर देखें
सही उत्तर: (A) Sodium pentacyanonitrosylferrate(III)
1 अंक · 2023 · सेट A
प्रश्न 84
Substance X is used in whitewashing and is obtained by heating limestone in the absence of air. Identify X.
उत्तर देखें
सही उत्तर: (C) CaO
1 अंक · 2023 · सेट A
प्रश्न 85
Dilute ferrous sulphate solution is gradually added to acidified permanganate solution. The light purple colour fades and disappears. Which explanation is correct?
उत्तर देखें
सही उत्तर: (A) KMnO₄ is an oxidizing agent and oxidizes FeSO₄.
1 अंक · 2023 · सेट A
प्रश्न 86
How many structural isomers are possible if one hydrogen atom in diphenylmethane is replaced by chlorine?
उत्तर देखें
सही उत्तर: (B) 4
1 अंक · 2023 · सेट A
प्रश्न 87
Which statement(s) is/are true? Prolonged exposure of silver chloride to sunlight turns it grey due to: (i) formation of silver by decomposition of silver chloride; (ii) sublimation of silver chloride; (iii) decomposition of chlorine gas from silver chloride; (iv) oxidation of silver chloride. Select the correct answer.
उत्तर देखें
सही उत्तर: (B) (i) and (iii)
1 अंक · 2023 · सेट A
प्रश्न 88
Which of the following is a branched polymer?
उत्तर देखें
सही उत्तर: (A) Low-density polymer
1 अंक · 2023 · सेट A
प्रश्न 89
Which monomers form biodegradable polymers?
उत्तर देखें
सही उत्तर: (D) More than one of the above
1 अंक · 2023 · सेट A
प्रश्न 90
The correct order of increasing nucleophilicity is
उत्तर देखें
सही उत्तर: (A) Cl⁻ < Br⁻ < I⁻
1 अंक · 2023 · सेट A
प्रश्न 91
Select the correct statement.
उत्तर देखें
सही उत्तर: (C) Spectroscopic methods require less time and less sample than classical methods.
1 अंक · 2023 · सेट A
प्रश्न 92
A carbonyl group causes a sharp dip at about _____ cm⁻¹.
उत्तर देखें
सही उत्तर: (A) 1700
1 अंक · 2023 · सेट A
प्रश्न 93
What is the best method for separating para- and ortho-nitrophenols from a 1:1 mixture?
उत्तर देखें
सही उत्तर: (C) Steam distillation
1 अंक · 2023 · सेट A
प्रश्न 94
Which compound undergoes nucleophilic substitution exclusively by an Sₙ1 mechanism?
उत्तर देखें
सही उत्तर: (A) Benzyl chloride
1 अंक · 2023 · सेट A
प्रश्न 95
Most phytophagous nematodes are
उत्तर देखें
सही उत्तर: (A) Root parasites
1 अंक · 2023 · सेट A
प्रश्न 96
One purpose of secondary treatment of wastewater and sewage is
उत्तर देखें
सही उत्तर: (B) To reduce BOD
1 अंक · 2023 · सेट A
प्रश्न 97
Most bacteria that cause plant diseases are members of which group?
उत्तर देखें
सही उत्तर: (B) Rod-shaped, Gram-negative bacteria
1 अंक · 2023 · सेट A
प्रश्न 98
Nutritionally, Albugo is a
उत्तर देखें
सही उत्तर: (C) Obligate parasite
1 अंक · 2023 · सेट A
प्रश्न 99
Which statement is incorrect?
उत्तर देखें
सही उत्तर: (C) Trees with large flowers and seeds are found in Compositae.
1 अंक · 2023 · सेट A
प्रश्न 100
One of the major Basmati rice-producing states in India is