In a series LR circuit, the inductive reactance is equal to the resistance R of the circuit. An emf \( E = E_0 \cos \omega t \) is applied to the circuit. The average power dissipated in one cycle is :

In Young's double slits experiment, the fringe width is found to be 0.2 mm for air medium. If the whole apparatus is immersed in water of refractive index 4/3 the new fringe width will be:

The radius of curvature of each surface of a double convex lens is 15 cm and the refractive index of the medium of the lens is 1.5. What is the focal length of the lens?

The ratio of energies of photons produced due to the transition of an electron of hydrogen atom from its
i. second permitted energy level to the first level and
ii. the highest permitted energy level to the first energy level is

Which of the following statement(s) is/are incorrect?
(A) The Kirchhoff's laws are equally applicable in alternating current circuit and direct current circuits.
(B) It is not necessary that the wire stretched on the meter bridge must have a uniform cross-sectional area.
(C) The internal resistance of the cell does not affect the reading of the null point in metre bridge.
(D) Electrical potential has no direction, the electrical potential gradient has a direction.

Two cells of emf 2 V and 4 V and internal resistance of \( 0.5 \text{ } \Omega \) each are connected with an external resistor of resistance \( 3 \text{ } \Omega \) as shown in the figure. The terminal potential difference of 2 V cell is:

A circular loop of area \(1 cm^2\), carrying a current of 10 A , is placed in a magnetic field of 0.1 T perpendicular to the plane of the loop. The torque on the loop due to the magnetic field is :

A 200 turns closely wound circular coil of radius 10 cm carries a current of 3.5 A. The magnetic moment of the coil is

Use of biofertilizers as a nutrient source is a practised in __________.

A charged particle moving with a certain velocity enters a uniform electric field perpendicular to its direction. In this context, which of the following statements are correct?
(A) Force acting on the particle is constant
(B) Acceleration of the particle is constant
(C) Velocity of the particle is constant
(D) Displacement of the particle follows a parabolic path
Choose the correct answer from the options given below:

A compound is formed by two elements X and Y.
Atoms of 'Y' make ccp and those of element 'X' occupy tetrahedral voids.
The formula of the compound is:

Read the passage carefully and answer the questions.
Amines are considered to be derivatives of ammonia obtained by replacement of hydrogen atoms with alkyl or aryl groups. They are usually prepared from nitro compounds, halides, amides, imides etc. The presence of hydrogen bonding influences its physical properties. In alkylamines, a combination of electron releasing steric and hydrogen bonding factors influences the stability of substituted ammonium cations in protic polar solvents and thus affects the basic nature of amines. Alkyl amines are found to be stronger bases than ammonia which is more basic than water. Primary and secondary amines are engaged in intermolecular association due to hydrogen bonding. This intermolecular association is more in primary amines than in secondary amines. Tertiary amines do not have intermoleulcar association due to the absenceof hydrogen atom available for hydrogen bonding. Thus, the boiling point of amines depends on hydrogen bonding. In aromatic amines, electron releasing and withdrawing groups increase and decrease their basic character. Aryl diazonium salts usually obtained from arylamine undergo replacement of the diazonium group with a variety of nucleophile. Their coupling reaction of aryl diazonium salts with phenol or arylamine results in formation of dyes.
Which of the following compounds will not undergo azo coupling with benzene diazonium chloride?

Read the following passage carefully.
Restriction enzyme
Restriction enzymes cut the strand of DNA a little away from the center of the palindrome sites, but between the same two bases on the opposite strands. This leaves single stranded portions at the ends. There are overhanging stretches called sticky ends on each strand. These are named so because they form hydrogen bonds with their complementary cut counterparts. This stickiness of the ends facilitates the action of the enzyme DNA ligase. The word palindromes refer to group of letters that forms the same words when read both forward and backward. Restriction endonucleases are used in genetic engineering as molecular scissors.
Which one of the following option is correct about restriction enzyme?