A lamp rating 8 V, 800 W is connected to a 100 V, 50 Hz a. c. source. The inductance of the choke required in the circuit is: (Take \( \pi = 3 \))

Two charges \( 5 \mu C \) and \( - 2 \mu C \) (with no external field) are placed at \( (-9 \text{ cm}, 0, 0) \) and \( (9 \text{ cm}, 0, 0) \) respectively. The work required to separate the two charges infinitely away from each other is :

The graph shows the variation of potential difference between the plates of two capacitors A and B with the increase of charge stored by them. From the graph we can conclude:

Which of the following statements are correct?
A. Dipole field depends on the distance r and also on the angle between the position vector and the dipole moment P
B. A comb runs through dry hair acquires charge through friction
C. If surface charge density of a plate is positive, the electric field is directed towards the plate.
D. Electrostatic field lines cannot form closed loops.
E. In a uniform electric field, a dipole experiences a torque and a net force also.
Choose the correct answer from the options given below:

A ray of light passes through an equilateral glass prism such that the angle of incidence (i) = angle of emergence (e). If the angle of emergence is 0.75 times the angle of the prism, the refractive index of the prism will be

When a current carrying coil is placed in a uniform external magnetic field with its magnetic moment antiparallel to the external magnetic field, then
(A) its potential energy is minimum
(B) its potential energy is maximum
(C) torque on it is maximum
(D) torque on it is zero
(E) coil is in unstable equilibrium
Choose the correct answer from the options given below:

Match List I with List - II.,

List - I	List - II
(A) TV Transmission	(I) Short wave bands
(B) Long distance radio broadcasts	(II) Microwave
(C) RADAR	(III) Infrared rays
(D) TV Remote	(IV) Satellite

Choose the correct answer from the options given below :

For the brown ring test, the correct order of the steps in the experiment is :
(A) Pour conc. \(H_2SO_4\) very slowly along the side of the test tube, very few drops of the acid should be poured.
(B) Take half spatula of the given salt in a dry test tube.
(C) Add 2 - 3 mL of freshly prepared ferrous sulphate solution to the test tube.
(D) Make a solution of the given salt.
Choose the correct answer from the options given below:

The large holes in 'Swiss cheese' are due to -

Read the passage carefully and answer the questions
Amines are considered as derivatives of ammonia obtained by replacement of hydrogen atoms with alkyl or aryl groups. In nature they occur among proteins, vitamins, alkaloids and hormones. These can be primary, secondary or tertiary depending on the number of hydrogen groups replaced. They can be prepared from nitro compounds, alkyl halides, nitriles, amides etc. Due to unshared pair of electrons they behave as Lewis bases. Influence of the number of hydrogen atoms at nitrogen atom is displayed in physical properties such as solubility, boiling point and chemical reactions including basicity. Basic character of amines is expressed in terms of their \(K_b\) and \(p K_b\) values. Three classes of amines can be distinguished with p-toluene sulphonyl chloride which reacts with primary and secondary ddu amines. Amino group when attached to benzene ring behaves as an activating and ortho para directing group.
Which amine will have highest \(p K _{ b }\) value?

A point charge q is placed at the center of a cube of side L. The total electric flux passing through any three faces of this cube is:

The rate constant for a zero order reaction was found to be \(1.0 \times 10^{-3} mol L ^{-1} s^{-1}\).
How long will 1.0 mol of the reactant take to reduce to 0.5 mol in one liter flask?

Answer the question on the basis of passage given below :
For the transition elements
Sc \(\quad\) Ti \(\quad\) V \(\quad\) Cr \(\quad\) Mn\(\quad\) Fe \(\quad\) Co \(\quad\) Ni \(\quad\) Cu \(\quad\) Zn
Atomic numbers :
21 \(\quad\) 22 \(\quad\) 23 \(\quad\) 24 \(\quad\) 25 \(\quad\) 26 \(\quad\) 27 \(\quad\) 28 \(\quad\) 29 \(\quad\) 30 \(\quad\)
Which transition metal has the greatest number of oxidation state?