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A series combination of n1 capacitors, each of value C1, is charged by a source of potential difference 4V. When another parallel combination of n2 capacitors, each of value C2, is charged by a source of potential difference V, it has the same (total) energy stored in it, as the first combination has. The value C2, in terms of C1, is?

E is the energy stored by a capacitor of capacitance C at the potential difference of V is E = 1/2CV2 We know that in the series... View Article

The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of the closed organ pipe is 20cm, the length of the open organ pipe is

The first is when the pipe is open at both ends, while the second is when the pipe is closed at one of the ends. The instrument is called an... View Article

A bulb is placed at a depth of 2√7m in water and a floating opaque disc is placed over the bulb so that the bulb is not visible from the surface. The radius of the disc should be at least (μ water =4/3) (Note, centre of disc is on the vertical line above the bulb) :

From the periphery, light should be internally reflected. For total internal reflection sinθ = μ1... View Article

A rectangular loop with a sliding connector of length=1.0m is situated in a uniform magnetic field field=2t perpendicular to the plane of loop. Resistance of the connector is r=2Ω . Two resistance is 6Ω and 3Ω are connected as shown in the figure. The external force required to keep the connector moving with a constant velocity v=2ms⁻¹

In this question it is given that, the resistance of the connector 2Ω magnetic field - 2t two resistance - 6Ω and 3Ω... View Article

A solenoid has a core of a material with relative permeability 400. The windings of the solenoid are insulated from the core and carry a current of 2A. If the number of turns is 1000 per meter, calculate (a) H, (b) B and (c) the magnetic current Im.

We have to calculate thethe magnetic field: B = μoμrnI ; Put the given values in the above equation and solve: B = 4π ×... View Article

The activation energy in a chemical reaction is defined as ?

The least amount of energy necessary for a reaction to occur is referred to as the activation energy. If the activation energy requirement is not... View Article

The molecule having zero dipole moment is: A. CHCl3 B. H2O C. CCl4 D. HCl

Answer: (c) CCl4 The property of an item having opposite physical characteristics at various sites is known as polarity. Magnetic... View Article

What would be magnetic moment of Gd+3(Z=64)?

Electronic configuration of [Gd]3+ :[Xe]4f7 Hence number of unpaired electron n=7 Hence, magnetic moment=n(n+2) = 63 = 7.9BM Magnetic... View Article

For an ideal solution, the correct option is: (A) ΔmixS=0 at constant T and P (B) ΔmixV≠0 at constant T and P (C) ΔmixH=0 at constant T and P (D) ΔmixG=0 at constant T and P

An ideal solution obeys Raoult's Law. According to the Raoult’s Law “For a solution of volatile liquids, the partial vapour pressure of each... View Article

If Z is the number of atoms in the unit cell that represents the closest packing sequence ABCABC, the number of tetrahedral voids in the unit cell is equal to:

Answer: 2Z The number of tetrahedral voids in closed packed ccp, fcc, and hcp is double the number of atoms (Z) composing the main lattice,... View Article

Explain biuret test for protein

Biuret is a chemical made by heating urea to 180 degrees Celsius. The Biuret test is a chemical test that uses the Biuret reagents, which include... View Article

Four metallic plates each with a surface area of one side A, are placed at a distance d from each other. The two outer plates are connected to one point A and the two other inner plates to another point B . Then the capacitance of the system is

Applying Gauss’s law to this closed surface, we get, ∮E.ΔA=Qen/ε0=σΔA/ε0 ⇒ EΔA =σΔA/ε0 ⇒ E = σ/ε0 = Q/Aε0 Now, the potential difference... View Article

The most stable free radical among the following is (1)C6H5CH2C˙H2(2)C6H5C˙HCH3(3)CH3C˙HCH3(4)C˙6H5

Answer: (2)C6H5C˙HCH3 We know that a radical's stability is determined by its intrinsic energy. If the radical's internal energy is very... View Article

Consider the ground state of Cr atom (Z = 24). The numbers of electrons with the azimuthal quantum numbers, l = 1 and 2 are, respectively:

There are four quantum numbers that we are all familiar with: The size of the electron cloud and the energy level of the electron are... View Article

Which of the following will not give an iodoform test? A. Ethanal B. Ethanol C. 2 – propanone D. 3 – pentanone

Answer:(D) 3 - pentanone The iodoform test is used to evaluate whether a carbonyl compound with the formula CH3C=O and a secondary alcohol... View Article

Which will make the basic buffer? A) 50 mL of 0⋅1 M NaOH + 25 mL of 0⋅1M CH3COOH B) 100 mL of 0⋅1 M CH3COOH + 100 mL of 0⋅1M NaOH C) 100 mL of 0⋅1 M HCl + 200 mL of 0⋅1M NH4OH D) 100 mL of 0⋅1 M HCl + 100 mL of 0⋅1M NaOH

Answer: (c) 100 mL of 0⋅1 M HCl + 200 mL of 0⋅1M NH4OH We'll start by learning about the fundamental buffer solution notion. The basic... View Article

The most reactive element in the halogen group is …………. A. Astatine B. Iodine C. Chlorine D. Fluorine

Answer: Fluorine On the periodic table, the halogens are to the left of the noble gases. Fluorine (F), chlorine (Cl), bromine (Br), iodine... View Article

A compound is formed by cation C and anion A. The anions form hexagonal close packed (HCP) lattice and the actions occupy 75% of octahedral voids. What is the formula of the compound?

Answer: C3A4 In hexagonal close packed (HCP) lattice, the number of atoms = 6 The number of atoms is always equal to the number of... View Article

The rate of a first order reaction is 0.04 molL⁻¹s⁻¹ at 10 seconds and 0.03 molL⁻¹s⁻¹ at 20 seconds after initiation of the reaction. What is the half-life period of the reaction?

We know that for a first-order reaction - K = 2.303/t2−t1.log[A]1/[A]2 Here, t2 = final time; [A]2 = final concentration t1 = initial time;... View Article

What is the maximum spin multiplicity for 4d-orbital? (a).4 (b).6 (c).5 (d).0

Answer: (b) 6 For the same spatial electronic wave-function, spin multiplicity is the number of possible orientations of the spin angular... View Article

M	T	W	T	F	S	S
	1	2	3	4	5	6
7	8	9	10	11	12	13
14	15	16	17	18	19	20
21	22	23	24	25	26	27
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