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The northern plains are formed by a) force of convection b) interplay of himalayan rivers c) glacier erosion

Answer: (a) By the interplay of three river systems Indus, Ganga, and the Brahmaputra The Northern Plain was formed by the deposits... View Article

The periodic time of a body executing SHM is 4s. After how much interval from time t=0, its displacement will be half of its amplitude?

Simple Harmonic Motion or SHM is defined as a motion in which the restoring force is directly proportional to the displacement of the body from... View Article

To obtain displacement current of 0.2 a between the plates of a capacitor of capacity 0.5 μf, what should be the rate of change of potential difference between the plates?

A capacitor is a two-terminal electrical device that possesses the ability to store energy in the form of an electric charge. It consists of two... View Article

What is the rest mass energy of electron?

The energy described by the Einstein equation is rest mass energy. The letter 'e' stands for electron charge. The letter M stands for mega, which... View Article

The oscillating magnetic field in a plane electromagnetic wave is given by: B_y=(8×10⁻⁶)sin[2×1011t+300πx]T (i) Calculate the wavelength of the electromagnetic wave. (ii) Write down the expression for the oscillating electric field.

Electromagnetic waves are also known as EM waves. Electromagnetic radiations are composed of electromagnetic waves that are produced when an... View Article

In the circuit shown below, the key K is closed at t=0. The current through the battery is

The inductor serves as an open switch at t = 0 since there is no current flowing through it. This occurs because, when the circuit's current... View Article

The mass of a lift is 500 kg. What will be the tension in its cable ifit moves down with an acceleration

Tension is a continual force that works on the connecting medium, such as a rope or cable. This is mostly a tugging force that attempts to... View Article

The maximum number of possible interference maxima for slit-separation equal to four times the wavelength in Young’s double-slit experiment is:

Answer: 9 Young's double-slit experiment employs two coherent light sources separated by a small distance. These two light sources are... View Article

The moment of inertia of a uniform circular disc of radius R and mass M about an axis passing from the edge of the disc and normal to the disc is

Moment of inertia is defined as the quantity expressed by the body resisting angular acceleration which is the sum of the product of the mass of... View Article

For a angular projection given to a projectile, find : (i) Maximum height, (ii) Time of flight, (iii) Horizontal range.

A projectile is any object thrown into space upon which the only acting force is gravity. The primary force acting on a projectile is gravity.... View Article

If the magnitude of two vectors are 4 and 6 and the magnitude of their scalar product is 12√2 , then what is the angle between these vectors?

A vector is a two-dimensional entity with both magnitude and direction. A vector can be visualised geometrically as a directed line segment with... View Article

A potential difference V is applied across a conductor of length ‘l’. How is the drift velocity affected when V is doubled and l is halved?

The formula for drift velocity is given by, |vd|=eτ/m x E But we know that E=V/l where V is the potential difference and l is the length... View Article

Assertion: In javelin throw, the athlete throws the projectile at an angle more than 45∘. Reason: The maximum range does not depend upon angle of projection. (A) Both assertion and reason are the correct answer, reason is the correct explanation for assertion. (B) Both assertion and reason are correct. The answer reason is the incorrect explanation for the assertion. (C) Assertion is correct and reason is incorrect. (D) Both assertion and reason are incorrect.

A javelin's route is identical to that of a projectile motion. So the formula of range in projectile motion is applicable. R=u2sin2θ/g sinθ... View Article

A current carrying power line carries current from west to east .The direction of magnetic field 1m above is:

Answer: North to south The direction of the magnetic field surrounding a straight current carrying wire is determined by the curling of the... View Article

Two identical glass (μg =3/2) equiconvex lenses of focal length f are kept in contact. The space between the two lenses is filled with water (μw =4/3). The focal length of the combination is

Water in between the lens can be considered to be a concave lens of refractive index of water as shown in the figure. This suggests that the... View Article

An AC current is given by I = I₀ + I₁ sinωt then the rms value will be.

Alternating current is the current whose magnitude varies with time and reverse it direction periodically, i.e. after half-time period. The rms... View Article

The resultant force on the square current loop PQRS due to a long current-carrying conductor will be:

The forces will be equal and opposed because the currents in the lengths PQ and RS are equal and opposite. As a result, both will cancel each... View Article

An equilateral triangular loop of wire of side ℓ carries a current i. The magnetic field produced at the circumcentre of the loop is :

If considered l is the triangle's side, the circumcenter's distance from each of the triangle's sides equals r= I√3/6. The magnetic induction... View Article

Two Magnets of equal magnetic moments M each are placed as shown in figure. The resultant magnetic moment isa) M b) √2M c) √3M d) M/2

Answer: (a)M Due to the fact that magnetic moments are directed along SN, the angle between M and M is equal to θ=120o (from given figure)... View Article

What is the correct relation between common base current gain α and common emitter current gain β ?

Answer: β = α/1−α We have asked to determine the relationship between the current gain α in Common Base CB mode and the current gain β in... View Article

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