The angular momentum of an electron moving in the circular path of diameter D in a uniform magnetic field \( B_0 \) is:

Four materials \(\mathrm{A}, \mathrm{B}, \mathrm{C}\) and D have the magnetic susceptibilities \(\chi_{m A}, \chi_{m B}, \chi_{m C}\) and \(\chi_{m D}\) respectively. which are related as \(\chi_{m D}<\chi_{m C}<\chi_{m B}<\chi_{m A}\). Which material can be magnetised with maximum ease?

Consider three long straight parallel wires as shown in the figure. Length of wire B is 25 cm. Choose the correct options based

(A) Net force experienced by wire B is \( 2 \times 10^{-4} \) N towards left
(B) Magnitude of repulsion force by wire A on B is \( 5 \times 10^{-4} \) N
(C) Magnitude of repulsion force by wire C on B is \( 2 \times 10^{-4} \) N
(D) Net force experienced by wire B is \( 2 \times 10^{-4} \) N towards right
Choose the correct answer from the options given below:

The speed of light in a medium whose critical angle is \(60^{\circ}\) will be:

A message signal of frequency \(\omega_m\) is superposed on a carrier wave of frequency \(\omega_c\) to get an amplitude modulated wave (AM). The frequency of the AM wave will be :

For transistor action, which of the following statements are correct?
A. Base, Emitter and Collector region have similar size and doping concentrations.
B. The base must be very thin and lightly doped.
C. The emitter junction is forward biased and the collector junction is reverse biased.
D. Both emitter and collector junction all forward biased.
Choose the correct answer from the options given below:

Five different waves travelling in the same direction are represented by: Choose the correct answer from the options given below for interference to take place:

Reaction of Chloroethane with ethanolic ammonia will result in :

Observe the illustration and answer the following question:

Arrange the following in order of their occurance in human female ovary.
A. Formation of secondary follicle
B. Mitotic division of oogonia
C. Formation of mature Graafian follicle
D. Maintenance of corpus luteum
Choose the correct answer from the options given below:

A telescope has an objective of focal length \(3 0 ~ c m\) and an eyepiece of focal length \(3 . 0 ~ c m\). It is focused on a scale distant 2.0 m . For seeing with relaxed eye, the separation between the objective and eyepiece would be:

The values of \(\lambda\) for which the following system of equations has unique solution:
\(\begin{array}{l}\lambda x+3 y-z=1 \\x+2 y+z=2 \\-\lambda x+y+2 z=-1\end{array}\)

Periodic abstinence is an example of:

Read the following passage carefully and answer the given questions.
The B-lymphocytes produce an army of proteins in response to pathogens. Each antibody molecule has four peptide chains, two small called light chains and two longer called heavy chains. Virus-infected cells secrete proteins called interferons which protect non-infected cells from further viral infection. Symptoms of allergic reactions include sneezing, watery eyes, running nose and difficulty in breathing. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Lymphoid organs are the organs where origin and/or maturation and proliferation of lymphocytes occur. The primary lymphoid organs are bone marrow and thymus. After maturation the lymphocytes migrate to secondary lymphoid organs like spleen, lymph nodes, tonsils, Peyer's patches of small intestine and appendix. Heroin commonly called smack is chemically diacetylmorphine which is a white, odourless, bitter crystalline compound. This is obtained by acetylation of morphine, which is extracted from the latex of poppy plant Papaver somniferum.
Which one of the followings drug does not reduce the symptoms of allergy quickly?