Electromagnetic waves are produced by

What is the force between two small charged spheres having charges of \( 4 \times 10^{-7} \text{ C} \) and \( 6 \times 10^{-7} \text{ C} \) placed 60 cm apart in air ?

The radius of curvature of the path of a charged particle in a uniform magnetic field is directly proportional to the

Two long and parallel straight conducting wires carrying currents of 5 A and 10 A in same direction are separated by a distance of 2 cm . The force per unit length on one wire due to other is \(\left(\mu_0: 4 \pi \times 10^{-7} N A ^{-2}\right)\)

What uniform magnetic field applied perpendicular to a beam of electrons moving at \( 1.3 \times 10^6 \text{ m/s} \) is required to make the electrons travel in a circular arc of radius 0.35 m?

Choose the correct statements from the following :
(A) A dielectric develops a net dipole moment in the presence of an electric field.
(B) Electrostatic potential is constant throughout the volume of the conductor.
(C) Electric field \( \vec{E} \) depends upon the distance between two thin infinite long uniformly charged plane sheets held parallel to each other.
(D) Electric field due to a uniformly charged spherical shell is zero at all points inside the shell.
(E) Electric field is in the direction in which the potential decreases steepest.

Displacement current exists only when

Let [t] denote the greatest integer ≤ t and aZ = {ax : x ∈ Z, a ∈ R} (where Z is set of integer and R is set of real number). The set of points of discontinuity of the function f(x) = [2x] is given by

Correct order of intermolecular forces of attractions in the following solids is :
(A) NaCl
(B) \(I_2\)
(C) Ice
(D) Iron
(E) Rubber
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Read the following passage carefully and answer the given questions.
Insulin consists of two short polypeptide chains- chain A and chain B, that are linked together by disulphide bridges. Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans, coleopterans and dipterans. Bt toxin protein is converted into an active form of toxin due to the alkaline pH of the gut which solubilise the crystals. Transgenic animals that produce useful biological products can be created by the introduction of the portion of DNA (or genes) which codes for a particular product such as human protein (alpha-1-antitrypsin) used to treat emphysema. Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called Genetically Modified Organisms (GMO). GM plants have been useful in many ways. Genetic modification has: (i) made crops more tolerant to abiotic stresses. (ii) reduced reliance on chemical pesticides (pest-resistant crops). (iii) helped to reduce post harvest losses. (iv) increased efficiency of mineral usage by plants (this prevents early exhaustion of fertility of soil). (v) enhanced nutritional value of food.
The beetles that infest Bt cotton plant are killed:

Identify, which is not the sexually transmitted infection?

A capacitor of \( 25 \mu \text{F} \) is connected in series with d.c Voltage of 5 V. The value of current in the circuit will be:

Which of the statements are true, If a convex lens is placed in water:
a. Its focal length increases.
b. Its focal length decreases.
c. Rays bend less when they move through lens.
d. There is no change in radius of curvature.
Choose the correct answer from the options given below :