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A body weighs 49 N on a spring balance at the north pole. What will be its weight recorded on the same weighing machine, if it is shifted to the equator?

[Use g = GM/R2 = 9.8 ms-2 and radius of earth, R = 6400 km.] a. 49 N b. 49.83 N c. 49.17 Nd d. 48.83 N Answer: (d) At North Pole, weight... View Article

If the source of light used in a Young’s double slit experiment is changed from red to violet:

a. the fringes will become brighter. b. consecutive fringe lines will come closer. c. the central bright fringe will become a dark fringe. d.... View Article

The logic circuit shown below is equivalent to :

The logic circuit shown below is equivalent to : Answer: (2) The answer is option 2... View Article

Match List – I with List-II.

Match List - I with List-II. List – I List - II (a) Source of microwave frequency ( i) Radioactive decay of nucleus (b)... View Article

When a particle executes SHM, the nature of graphical representation of velocity as a function of displacement is:

a. elliptical b. parabolic c. straight line d. circular Answer: (a) We know that in SHM; V = ω√(A2 - x2) Elliptical Alternate: x = A... View Article

Given below are two statements: Statement I: PN junction diodes can be used to function as transistor, simply by connecting two diodes, back to back, which acts as the base terminal. Statement II: In the study of transistor, the amplification factor β indicates ratio of the collector current to the base current.

In the light of the above statements, choose the correct answer from the options given below. a. Statement I is false but Statement II is true.... View Article

A circular hole of radius (a/2) is cut out of a circular disc of radius ‘a’ shown in figure. The centroid of the remaining circular portion with respect to point ‘O’ will be:

A circular hole of radius (a/2) is cut out of a circular disc of radius ‘a’ shown in figure. The centroid of the remaining circular... View Article

On the basis of kinetic theory of gases, the gas exerts pressure because its molecules:

a. suffer change in momentum when impinge on the walls of container. b. continuously stick to the walls of container. c. continuously lose... View Article

An X-ray tube is operated at 1.24 million volt. The shortest wavelength of the produced photon will be:

a. 10-2 nm b. 10-3 nm c. 10-4 nm d. 10-1 nm Answer: (b) The minimum wavelength of photon will correspond to the maximum energy due to... View Article

According to Bohr atom model, in which of the following transitions will the frequency be maximum?

a. n = 2 to n = 1 b. n = 4 to n = 3 c. n = 5 to n = 4 d. n = 3 to n = 2 Answer: (a) Since, ΔE is maximum for the transition from n = 2 to... View Article

Zener breakdown occurs in a p-n junction having p and n both:

a. lightly doped and have wide depletion layer. b. heavily doped and have narrow depletion layer. c. heavily doped and have wide depletion layer.... View Article

Dichromate ion is treated with base, the oxidation number of Cr in the product formed is:

Answer: 6 Cr2O72- + 2OH- ⇌ 2CrO42- + H2O For CrO42- x + (–2 × 4) = –2 x = 6... View Article

A homogeneous ideal gaseous reaction AB_2(g) ⇌ A_(g) + 2B_(g) is carried out in a 25 liter flask at 27^oC. The initial amount of AB₂ was 1 mole and the equilibrium pressure was 1.9 atm. The value of K_p is x × 10^–2. The value of x is ______. [R = 0.08206 dm³ atm K^–1 mol^–1]

Answer: 74 The answer is 74... View Article

A certain gas obeys P(V_m – b) = RT. The value of (∂Z/∂P)_T is xb/RT. The value of x is ______.
Answer: 1 P(v – b) = RT PV – Pb = RT Z = 1 + PV/RT dZ/dP = 0 + b/RT b/RT = xb/RT x = 1... View Article

For a chemical reaction A +B ⇌ C + D (Δ_rH^ψ = 80 kJ mol^–1) the entropy change Δ_rS^ψ depends on the temperature T (in K) as Δ_rS^ψ = 2T (J K^–1 mol^–1). Minimum temperature at which it will become spontaneous is ________K.

For a chemical reaction A +B ⇌ C + D (ΔrHψ = 80 kJ mol–1) the entropy change ΔrSψ depends on the temperature T (in... View Article

Number of bridging CO ligands in [Mn₂(CO)₁₀] is _____.
Number of bridging CO ligands in [Mn2(CO)10] is _____. Answer: 0 Fact Hence the answer is 0... View Article

The number of significant figures in 50000.020 × 10^–3 is _______.
Answer: 7 50000.020 × 10–3 Number of significant figures = 7... View Article

3.12 g of oxygen is adsorbed on 1.2 g of platinum metal. The value of oxygen adsorbed per gram of the adsorbent at 1 atm and 300 K in L is _______.
[R = 0.0821 L atm K–1 mol–1] Answer: 2 Moles of O2 = 3.12/32 = 0.0975 volume of O2 = nRT/P = (0.0975 ×0.082×300)/1 volume... View Article

Consider the following reaction
Consider the following reaction MnO4- + 8H+ + 5e– → Mn+2 + 4H2O, Eo = 1.51 V. The quantity of electricity required in Faraday to... View Article

224 mL of SO_2(g) at 298 K and 1 atm is passed through 100 mL of 0.1 M NaOH solution. The non-volatile solute produced is dissolved in 36 g of water. The lowering of vapour pressure of solution (assuming the solution is dilute) (P(H₂O)= 24 mm of Hg) is 10^–2 x mm of Hg, the value of x is _____

Answer: 0.18 The balanced equation is SO2 + 2NaOH → Na2SO3 + H2O moles of NaOH = molarity × volume (in litre) = 0.1 × 0.1 = 0.01... View Article

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