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The figure shows a circuit that contains four identical resistors with resistance R = 2.0 Ω. Two identical inductors with inductance L = 2.0 mH and an ideal battery with emf E = 9.V. The current ‘i’ just after the switch ‘s’ is closed will be:

The figure shows a circuit that contains four identical resistors with resistance R = 2.0 Ω. Two identical inductors with... View Article

In the given figure, a body of mass M is held between two massless springs, on a smooth inclined plane. The free ends of the springs are attached to firm supports. If each spring has spring constant k, the frequency of oscillation of given body is:

  a. (1/2π) √(2K/Mg sin α) b. (1/2π) √(K/Mg sin α) c. (1/2π) √(2K/M) d. (1/2π) √(K/2M) Answer: (a) Equivalent... View Article

The period of oscillation of a simple pendulum is T = 2π√(L/g). Measured value of ‘L’ is 1.0 m from meter-scale having a minimum division of 1 mm and time of one complete oscillation is 1.95 s measured from stopwatch of 0.01 s resolution. The percentage error in the determination of ‘g’ will be:

a. 1.33 % b. 1.30 % c. 1.13 % d. 1.03 % Answer: (c) T = 2π√(L/g) T2 = 4... View Article

If one mole of an ideal gas at (P₁, V₁) is allowed to expand reversibly and isothermally (A to B) its pressure is reduced to one-half of the original pressure (see figure). This is followed by a constant volume cooling till its pressure is reduced to one-fourth of the initial value (B→C). Then it is restored to its initial state by a reversible adiabatic compression (C to A). The net work done by the gas is equal to:

If one mole of an ideal gas at (P1, V1) is allowed to expand reversibly and isothermally (A to B)... View Article

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... 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... 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

Match List – I with List-II.

Match List – I with List-II. List – I List – II (a) Source of microwave frequency ( i) Radioactive... 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 –... 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... 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... 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.... 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... 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... 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... 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 =... 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]

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.