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In a series RLC circuit that is operating above the resonant frequency, the current A. lags the applied voltage B. leads the applied voltage C. is in phase with the applied voltage D. is zero

The capacitive and inductive reactances are equivalent at resonance. The inductive reactance will be stronger than the capacitive reactance above... View Article

The uncertainty in the position of an electron (mass = 9.41 x 10⁻²⁹g) moving with a velocity of 3.0 X 10⁴cm⁻¹ accurate up to 0.011 percent will be

In quantum mechanics, the Heisenberg uncertainty principle is a fundamental theory which explains why it is important to measure more than one... View Article

Which of the following statements in relation to the hydrogen atom is correct? (a) 3s, 3p and 3d orbitals all have the same energy (b) 3s and 3p orbitals are of lower energy than 3d orbital (c) 3p orbital is lower in energy than 3d orbital (d) 3s orbital is lower in energy than 3p orbital

Answer (a) 3s, 3p, and 3d orbitals all have the same In the 1s orbital of a hydrogen atom, there is just one electron. As a result, it is not... View Article

Using the standard electrode potential, find out the pair between which redox reaction is not feasible.E∘ values: Fe³⁺/Fe²⁺= +0.77; I2/I−= +0.54; Cu⁺²/Cu= +0.34; Ag⁺/Ag= +0.80V (A) Fe⁺³ and I⁻ (B) Ag⁺ and Cu (C) Fe⁺³ and Cu D) Ag⁺ and Fe⁺³

Answer: (d) The reduction potential for various elements: Fe3+/Fe2+ = +0.77 V I2/I− = +0.54 V Cu+2/Cu = +0.34... View Article

An electron is revolving around a proton in a circular orbit of diameter 1A∘. If it produces a magnetic field of 14 Wb/m2 at the proton, then its angular velocity will be about

In a circular orbit with a diameter of 1A, an electron revolves around a proton. If we are asked to calculate the angular velocity of a proton... View Article

A very broad elevator is going up vertically with a constant acceleration of 2m/s² . At the instant when its velocity is 4m/s a ball is projected from the floor of the lift with a speed of 4m/s , relative to the floor at an elevation of 30⁰ . The time taken by the ball to return the floor is

The component of the velocity of the ball relative to the elevator is In the x-direction, the component of velocity is vx = 4cos300=2√3m/s In... View Article

What are the total number of pi and sigma bonds in naphthalene C10H8?

Carbon atoms make up the majority of organic compounds. As a result, the bonds are generally made up of two types of bonds: sigma () and pi().... View Article

200 ml of He at 0.66 atm pressure and 400 ml of O2 at 0.52 atm pressure are mixed in a 400 ml vessel at 25degreeC. The partial pressure of He and O2 will be:

Partial pressure is the pressure of an individual gas when it is placed in a required vessel or in the final vessel. Initially volume... View Article

For 50ml of hydrogen diffuses through a small hole in 20 minutes. The time taken for 40ml of oxygen to diffuse under the same conditions in minutes is:

The movement of certain particles or anything from a high concentration area to a low concentration area is known as diffusion. Diffusion is... View Article

A length of wire carries a steady current. It is bent first to form a circular plane of coil of one turn. The same length is now bent more sharply to give a double loop of smaller radius. The magnetic field at the centre caused by the same current is (A) a quarter of its first value (B) unaltered (C) four times of its first value (D) half of its first value

Answer: (C) four times of its first value We know that the magnetic field is given as: ⇒ B = μ0nI/2R For the initial case, let us assume a... View Article

A galvanometer can be converted into a voltmeter by connecting: A. Low resistance in parallel B. Low resistance in series C. High resistance in parallel D. High resistance in series

Answer: D. High resistance in series A large resistance is connected in series with a galvanometer to convert it to a voltmeter. Because a... View Article

What is biasing a diode?

In general, biassing is described as a configuration in a diode or an electrical device that allows for a greater flow of current in one... View Article

Which of the following substances is antiferromagnetic? (a).MnO (b).CrO2 (c).Fe3O4 (d).NaCl

Answer: (a) MnO Antiferromagnetism is a property of MnO. Antiferromagnetism is a kind of solid magnetism in which neighbouring ions behave... View Article

The solubility product of Ag2CrO4 is 2.6×10⁻² at 25∘C. Calculate the solubility of the compound.

A precipitate may or may not occur when two electrolytic solutions are mixed. Two criteria are reviewed in order to assess whether a precipitate... View Article

Correct order of polarizing power is: A. Cs⁺ < K⁺ < Mg²⁺ < Al³⁺ B. Al³⁺ < Mg²⁺ <K⁺< Cs⁺ C. Mg²⁺ < Al³⁺ < K⁺< Cs⁺ D. K⁺ < Cs⁺ < Mg²⁺ < Al³⁺

Answer: (a) Polarising power is the extent to which a cation can polarise an anion. It is proportional to charge density. Charge density is... View Article

A particle has a displacement of 12 m towards east then 5 m towards north and then 6 m vertically upward. The resultant displacement is: A) 10.04 m B) 12.10 m C) 14.32 m D) 12.6 m

Given that d1=12m d2=5m d3=6m Now, we will find the resultant displacement of the particle due to its motion of 12 m towards east and 5 m... View Article

A long straight wire in the horizontal plane carries a current of 50A in north to south direction. Find the magnitude and direction of B at a point 2.5m east of the wire.

Formula used: B=μ0I/2πr. As we already know that for an infinite conductor, the magnetic field B at a perpendicular distance r is equal... View Article

The interstitial hole is called tetrahedral why?

Each sphere of the second layer touches three spheres of the first layer in hexagonal close packing (hcp) and cubic close packing (ccp). As a... View Article

An electric dipole of length 1cm which is kept with its axis making an angle of 60∘ with a uniform electric field, experiences a torque of 6√3Nm. Calculate the potential energy of the dipole if it has charge ±2nC.

The length of the electric dipole is given as, l = 1cm The angle at which the dipole is placed from the axis is given as, θ = 60∘... View Article

A concave mirror of focal length 10cm is placed at a distance of 35cm from a wall. How far from the wall should an object be placed so that its real image is formed on the wall?

Focal length of the mirror is 10 cm Distance of the object from the wall is 35 cm Now, we want to get the real image of the object on the wall.... View Article

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