A point source of light is placed at a distance twice the focal length of a converging lens. If the focal length of the lens is f, the intensity of the image of light source on the other side of the lens will be maximum at

A deutron and an \(\alpha\)-particle moving with the same velocity enter into a uniform magnetic field acting normal to the plane of their motion. The ratio of the circular paths described by the deutron and \(\alpha\)-particle is

Match List-I with List-II

List-I	List-II
(A) \( \oint {B} \cdot d{s} = 0 \)	(I) magnetic field lines
(B) Directional property of freely suspended magnet	(II) circulating ions
(C) Never intersect each other	(III) torque on magnetic dipole
(D) Magnetic field of earth	(IV) monopoles in magnetism do not exist

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.

Width of two slits in Young's double slits experiment are in the ratio 9:4.
The ratio of the amplitudes of light waves through them would be:

Which of the following examples are based upon the total internal reflection of light?
(A) Optical fibre
(B) Twinkling of stars
(C) Mirage
(D) Sparkling of diamond
Choose the correct answer from the options given below:

A 100 m long antenna is mounted on a 25 m tall building. The complex can become a transmission tower for waves with wavelength nearly equal to :

In an AC generator, a coil of 20 turns each with area \( 2 \times 10^{-2} \text{ m}^2 \) is rotated at 50 revolutions per sec in a uniform magnetic field of 2.5 T. The maximum induced emf produced is:

A light with an energy flux of 25 \( W/cm^2 \) falls on a non-reflecting surface at normal incidence. If the surface has an area of 50 \( cm^2 \) and the total energy falling on the surface is \( 10 \times 10^5 \) J. The total duration of time of the incidence of light is

\(\lim _{x \rightarrow \infty}\left(\frac{x+7}{x+1}\right)^x\) is equal to:

The value of the integral \(\int\left(x^6+x^4\right) d\left(x^2\right)\) is equal to:

Read the passage carefully and answer
Carbohydrates are essential for both plants and animals. Some common examples of carbohydrates are glucose, fructose, sucrose, glycogen, cellulose and starch. They form a major portion of our food. Honey has been used for a long time as an instant source of energy in Ayurvedic medicine. Carbohydrates are used as storage molecules in both plants and animals. The cell wall of bacteria and plants is made of cellulose. We use cellulose in the form of wood for making furniture and as cotton fiber for clothing. They also provide raw material for textiles, paper, lacquers, and breweries. Carbohydrates are classified as Monosaccharides, Oligosaccharides and Polysaccharides on the basis of their behavior towards hydrolysis. Monosaccharides cannot be hydrolyzed further to simpler units whereas oligosaccharides can yield 2-10 units of monosaccharides on hydrolysis. Polysaccharides, which are non-sugars yield a large number of monosaccharide units on hydrolysis.
Answer the following questions about carbohydrates:
Pick the incorrect statement from the following:

Two points A and B in a plane are related if OA = OB, where O is a fixed point. This relation is: