A common emitter amplifier has a current gain 75. The collector resistance is 4 \( k\Omega \) and the input resistance is 500 \( \Omega \). The voltage gain of amplifier is:

The resistance of a cylindrical conductor is :

Identify the correct statements from the following in the context of electromagnetic waves.
(A) X-rays are not electromagnetic waves.
(B) Electromagnetic waves are transverse in nature.
(C) Electromagnetic waves can not be polarised.
(D) Electromagnetic waves travel with the speed of light in vacuum.
Choose the correct answer from the options given below:

A short bar magnet placed with its axis at \(30^\circ\) with a uniform external magnetic field of 0.24 T experiences a torque of magnitude 0.048 N m. The magnetic moment of the magnet is

Identify the correct statements
(A) Electric current arises due to the continuous flow of electrons or ions.
(B) A current flows through a conductor only when there is an electric field within the
conductor.
(C) The drift velocity of electrons is directly proportional to the applied electric field.
(D) The average thermal velocity of the electrons in a conductor is zero.
(E) In the absence of an electric field, the electrons in a conductor are at rest.
Choose the correct answer from the options given below :

Which of the following statement is correct for a potentiometer ?

The work function of a photoelectric surface is 3.3 eV. The value of the threshold frequency for the surface is :

Read the following paragraph and answer the given questions.
Cancer detection is based on biopsy and histopathological studies. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs. Do you know why mother's milk is considered very essential for the new-born infant? The yellowish fluid colostrum secreted by mother during the initial days of lactation has abundant antibodies (IgA) to protect the infant. Different species of Plasmodium (P. vivax, P. malaria and P. falciparum) are responsible for different types of malaria. Of these, malignant malaria caused by Plasmodium falciparum is the most serious one and can even be fatal. The exaggerated response of the immune system to certain antigens present in the environment is called allergy. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Drugs like barbiturates, amphetamines, benzodiazepines, and other similar drugs, that are normally used as medicines to help patients cope with mental illnesses like depression and insomnia, are often abused. Morphine is a very effective sedative and painkiller, and is very useful in patients who have undergone surgery.
Which type of drug cannot quickly reduce the symptoms of allergy?

The ratio of velocity of light in vacuum to that of velocity of light in medium is: (where symbols have their usual meanings).

Arrange the steps of DNA Fingerprinting in a correct sequence:
(A) Digestion of DNA by restriction endonucleases
(B) Hybridisation using labelled VNTR probe and detection of hybridized DNA by autoradiography
(C) Isolation of DNA
(D) Separation of DNA fragments by electrophoresis and blotting
Choose the correct answer from the options given below:

Read the passage carefully and answer the questions
Nearly all the transition elements display typical metallic properties such as high tensile strength, ductility, malleability, high thermal and electrical conductivity and metallic lustre. The transition metals (with the exception of Zn, Cd and Hg) are very hard and have low volatility. Their melting and boiling points are high. They have high enthalpies of atomization. lons of the same charge in a given series show progressive decrease in radius with increasing atomic number. However, the variation within a series is quite small. The filling of 4f before 5d orbital results in a regular decrease in atomic radii called Lanthanoid contraction which essentially compensates for the expected increase in atomic size with increasing atomic number. The net result of the lanthanoid contraction is that the second and the third d series exhibit similar radii (e.g., Zr 160 pm, Hf 159 pm) and have very similar physical and chemical properties. There is an increase in ionisation enthalpy along each series of the transition elements from left to right. The first ionisation enthalpy, in general, increases, but the magnitude of the increase in the second and third ionisation enthalpies for the successive elements, is much higher along a series. One of the notable features of a transition elements is the great variety of oxidation states these may show in their compounds.
Atomic number of \(\mathrm{V}, \mathrm{Mn}, \mathrm{Cu}\) and Zn is \(23,25,29\) and 30 respectively. Which of them shows a positive value for the standard electrode potential \(E^{\circ}\left(M^{2+} / M\right)\) ?

The A and B polypeptides chains in insulin are linked together by which bond?

Choose the wrong statement.