If the forward voltage in a p-n junction diode is increased, the width of the depletion region :

Which of the following statements are correct?
(A) Magnetic susceptibility is defined as ratio of Intensity of magnetisation to magnetic field intensity.
(B) Magnetic susceptibility is a ratio of similar quantities therefore has no unit.
(C) The value of magnetic susceptibility for vacuum is one.
(D) Greater is the value of intensity of magnetisation, smaller is the value of susceptibility.
(E) Smaller is the value of magnetic field intensity, smaller is value of susceptibility.
Choose the correct answer from the options given below :

In a photoelectric experiment, the wavelength of incident light is increased from \( 5 \times 10^{-10} \text{ m} \) to \( 9 \times 10^{-10} \text{ m} \), while the intensity of radiation remains the same. Choose the correct statement from the following.

A cell of emf E is connected across an external resistance R. When a current I is drawn, the potential difference across the electrodes drops to V. The internal resistance r of the cell is :

Identify the important features of the semiconductor devices from the following
1. Semiconductor devices require cathode heating for the production of charge carriers.
2. They have long life and high reliability.
3. They are small in size and consume low power.
4. They operate at high voltage.
Choose the correct answer from the options given below:

Identify the correct statements among the following:
(A) The value of the electrostatic force constant, k depends on the medium between the two charges and on the choice of system of units.
(B) For two positively charged bodies, one more highly charged than the other, the force between them may be attractive.
(C) The charge on a body does change with its velocity.
(D) An electric dipole is a pair of two equal and similar charges placed at a very small distance.

A total of \(5.0 \times 10^{16}\) electrons per second go through a conductor of area \(2 mm^2\). The current density will be:

For an ammeter, voltmeter and galvanometer having resistances \( R_A, R_V \) and \( R_G \) respectively, the correct relation among these resistances:

Which of the following differential equation represents the family of circles touching the \(x\)-axis at the origin?

A ferromagnetic core of susceptibility 799 is subjected to a magnetizing field. The permeability of the material is (Take \( \mu_0 = 4\pi \times 10^{-7} \, \text{T m A}^{-1} \))

Which of the following statements are true?
(A) Rheostat can be used both as a variable resistance and a potential divider.
(B) An electrical circuit is functional only if all the components of the circuit are connected in proper order, assuming that all circuit components/ devices are in working condition and key is closed.
(C) An open circuit means a break in some part of a circuit which could be deliberate such as a key in open position or a fault such as broken wire or burnt out component(s) or loose connection.
(D) Rheostat as a potential divider gives variable resistance.
Choose the correct answer from the options given below:

Interference was observed in a chamber where air was present. Now, the chamber is evacuated and the same light is used. A careful observer will note :

Read the passage carefully and answer the given questions.
Recombinant DNA Technology
Asexual reproduction preserves the genetic information, while sexual reproduction permits variation. Traditional hybridization procedures used in plants and animals breeding very often lead to inclusion and multiplication of undesirable genes along with the desired genes. The techniques of genetic engineering, which include creation of recombinant DNA, use of gene cloning and gene transfer, overcome this limitation and allow us to isolate and introduce only one or a set of desirable genes without introducing genes into the target organism.
Which one of the following techniques is used to amplify a specific DNA
sequence?