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Which of the following is/are correct regarding root mean square speed (U_rms) & average translation K.E. (E_av) of molecule in a gas at equilibrium.

a) Eav is doubled when its temperature is increased 4 times b) Urms is inversely proportional to the square root of its molecular mass c) Eav... View Article

Identify the option where all four molecules possess permanent dipole moment at room temperature.

a) BF, O3, SF6, XeF6 b) BeCl2, CO2, BCl3, CHCl3 c) SO2, C6H5Cl, H2Se, BrF5 d) NO2, NH3, POCl3, CH3Cl Answer: (c, d) For Option c... View Article

Which of the following are true.

a) Monosachharides can not be hydrolysed to give polyhydroxy aldehydes and ketones. b) Oxidation of glucose with bromine water gives glutamic... View Article

Choose the corection option for the following reaction

Answer: (1, 4)... View Article

Fusion of MnO₂ along with KOH and O2 forms X. Electrolytic oxidation of X yields Y. X undergoes disproportionation reaction in acidic medium to MnO2 and Y. The Manganese in X and Y is in the form W & Z respectively, then

a) W & Z are coloured b) W is diamagnetic and Z is paramagnetic c) Both W & Z are tetrahedral in shape d) Both W & Z involve pπ-dπ... View Article

In the given reaction, x1, x2, x3, x4 are either particles or radiation.

Which of the given options is correct? a) x1 is deflected toward negatively charged plate. b) x2 is β-particle. c) x3 is γ-radiation. d) z is... View Article

A Tin-chloride ‘P’ gives following reaction (unbalanced reaction)

P + Cl- X [Monoanion pyramidal geometry] P + Me3N Y P + CuCl2 Z + CuCl Then which of the following is/are correct. a) Y contains... View Article

Choose the reaction, for which the standard enthalpy of reaction is equal to the standard enthalpy of formation:

Answer: (B, C) By definition, Enthalpy of formation is defined as the Enthalpy change occurring when, a compound is formed from its... View Article

Which green coloured compound of chromium is formed in borax bead test?

a) Cr(BO2)3 b) Cr2O3 c) CrB d) CrBO3 Answer: (a)... View Article

The correct order of acid strength of the following carboxylic acids is

Answer: (1)... View Article

Which of the following set represent correct formula for Malachite, Magnetite, Calamine & Cryolite?

a) CuCO3, Fe2O3, ZnO, Al2O3 b) CuCO3,Cu(OH), Fe3O4, ZnCO3, Na3 AlF6 c) CuCO3, Fe3O4, ZnCO3, Al2O3 d) CuCO3.Cu(OH), Fe2O3, ZnCO3, Na3AlF6... View Article

The balancing length for a cell is 560 cm in a potentiometer experiment. When an external resistance of 10 Ω is connected in parallel to the cell, the balancing length changes by 60 cm. If the internal resistance of the cell is N/10 Ω, the value of N is

Answer.(12) Let the emf of cell is Ɛ internal resistance is r and potential gradient is x. Ɛ = 560 x …(i) After connecting the resistor... View Article

The sum of two forces [latex]\vec{P}[/latex] and [latex]\vec{Q}[/latex] is [latex]\vec{R}[/latex] such that [latex]\vec{R}[/latex] = |P|[latex]\left | \vec{R} \right | = \left | \vec{P} \right |[/latex]. The angle θ (in degrees) that the resultant of [latex]\vec{2P}[/latex] and [latex]\vec{Q}[/latex] will make with [latex]\vec{Q}[/latex] is __

Answer: (90°)... View Article

Consider a uniform cubical box of side a on a rough floor that is to be moved by applying minimum possible force F at a point above its centre of mass (see figure). If the coefficient of friction is μ = 0.4, the maximum value of 100 ×b/a for the box not to topple before moving is __.

Answer: (50) F balances kinetic friction so that the block can move So, F = μmg For no toppling, the net torque about bottom right edge... View Article

M grams of steam at 100⁰C is mixed with 200g of ice at its melting point in a thermally insulated container. If it produces liquid water at 40⁰C[heat of vaporization of water is 540 cal/g and heat of fusion of ice is 80 cal/g ], the value of M is __.

Answer:(40) Here, heat absorbed by ice = mice Lf + mice Cw(40-0) Heat released by steam = msteam Lv + msteam Cw(100-40) Heat absorbed = heat... View Article

A 60 pF capacitor is fully charged by a 20 V supply. It is then disconnected from the supply and is connected to another uncharged 60 pF capacitor in parallel. The electrostatic energy that is lost in this process by the time the charge is redistributed between them is __(in nJ)

Answer: (6) V0 = 20 V Initial potential energy Ui = ½ CV02 After connecting identical capacitor in parallel, voltage across each... View Article

The dimension of B²/2μ₀ where B is magnetic field and μ₀ is the magnetic permeability of vacuum, is

a. ML-1T-2 b. ML2T-2 c. MLT-2 d. ML2T-1 Answer: (a) Energy density in magnetic field = B2/2 μ0 = force ×displacement/(displacement)3 =... View Article

An emf of 20 V is applied at time t = 0 to a circuit containing in series 10 mH inductor and 5 Ω resistor. The ratio of the currents at time t = ∞ and t = 40 s is close to take e²= 7.389)

a. 1.06 b. 1.46 c. 1.15 d. 0.84 Answer: (a) i = i0( 1- e-t/L/R) = (20/5)( 1-e-t/0.01/5) = 4(1-e-500t) i∞ = 4 i40 = 4(1 - e-500×40) = 4(... View Article

The figure gives experimentally measured B vs H variation in a ferromagnetic material. The retentivity, coercivity and saturation, respectively, of the material are

a. 1.5 T, 50 A/m, 1 T b. 1 T, 50 A/m, 1.5 T c. 1.5 T, 50 A/m, 1 T d. 150 A/m, 1 T, 1.5 T Answer: (b) x = retentivity y = coercivity... View Article

An elevator in a building can carry a maximum of 10 persons, with the average mass of each person being 68 kg. The mass of the elevator itself is 920 kg and it moves with a constant speed of 3 m/s. The frictional force opposing the motion is 6000N. If the elevator is moving up with its full capacity, the power delivered by the motor to the elevator (g = 10 m/s²) must be atleast

a. 66000 W b. 63360 W c. 48000 W d. 56300 W Answer: (a) Net force on motor will be Fm = (920 + 68(10)]10 + 6000 = 22000 N So, required... View Article

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