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HEY, HAVE U HEARD THIS,,, THE IIT ROORKEE CUTOFFS ARE FALLEN TO A VAST EXTENT LIKE BELOW 05 PER SUBJECT....THIS NEWS I READ IN THE HINDU NEWSPAPER A COUPLE OF WEEKS AGO PLZ CHECK OUT AND CONFIRM
IT LL BE USEFUL TO ALL OF US!!

mesomeric effect is related to optical activity and resonance is something diff.

as the meso effect increases, optical character of the compound is meant to decrease. meso-compounds are optically inactive. compounds which can undergo resonance are more stable. mmoreover, resonance is related only to carbon atoms.
mesomers are compounds which when put in front of a mirror, look different from the original. the can rotate about the main C--------C axis to form compounds with varying physical & chemical properties.
resonance does not alter the basic properties of the compound, it inly increases the stability.

ring exp takes place for acquiring stability to the ring compound, no matter it isan alkane, or alkene, etc..

stability of cation is of the order: tert>sec>pri carbocation.

whenever there is a chance to form a more stable c-cation,
the existing bond breaks at a point thereby forming a c-cation there, and the electron finds room nd attaches to another c-atom...
i just entered into my XII th and im a learner, i have shared my knowledge.Viewers, if m y explanation was not apt, plz give me the right one.

check out with max no of alpha hydrogens attached to carbon atom. i think the proceeedure is same!

3-chloro-4,6,6-trimethylbicyclo[3.1.1]heptane

there is a method of naming these bicyclo and spiro compounds...i guess you know them!!

phenyl carbocation is the most unstable coz order of stability of c-cations is something like-
benzyl>allyl>tertiary>secondary>primary>methyl>vinyl>phenyl...i suppose im right...if im wrong plz supply me with the rite answer

calculations too lengthy you get something like x^4+6x^3+.....=0

this point is the so mentioned drawback of newton's inverse square law and this concept of gravitation.
as said by others,it might even be due to the gravitons which enable attraction b/w the particles
newton actually was unable to support his concept that grav. force is n attractive force.

maybe.. when it is left empty, time peroid decreases coz...something like a low pressure develops inside the bob, air gushes inside it, and probably the tim period decreases due to the effect of atmospheric pressure on the bob thereby decreasing the amplitude of oscillation!

and when water is filled, i think the net wt of bob increases, the restoeing force(mg sin theeta) increases and the amplitude increases and so the time period of oscillation increases

hey, im a learner i might even be wrong but i mostly dont think so..)

Q. 2

If 0 < x < 1 , then

1.

2.

x

3.

4.

Q. 3

The edges of a parallelopiped are of unit length and are parallel to non-coplanar unit vectors

Then, the volume of the parallelopiped is

Q. 4

Let a and b be non-zero real numbers. Then the equation (ax² + by² + c)(x² - 5xy + 6y²) represents

1.

four straight lines, when c = 0 and a, b are of the same sign

2.

two straight lines and a circle, when a = b, and c is of sign opposite to that of a

3.

two straight lines and a hyperbola, when a and b are of the same sign and c is of sign opposite to that of a

4.

a circle and an ellipse, when a and b are of the same sign and c is of sign opposite to that of a

Q. 5	Let and n are integers, m 0 , n > 0 and let p be the left hand derivative of

	1.	n = 1 , m = 1

	2.	n = 1 , m = -1

	3.	n = 2 , m = 2

	4.	n > 2 , m = n

Paragraph for Question Nos. 41 to 43

In a mixture of H - He⁺ gas (He⁺ is singly ionized He atom), H atoms and He⁺ ions are excited to their respective first excited states. Subsequently, H atoms transfer their total excitation energy to He⁺ ions (by collisions). Assume that the Bohr model of atom is exactly valid.

Ques. The quantum number n of the state finally populated in He⁺ ions is

1.

2

2.

3

3.

4

4.

5

4 marks

Q. 42

The wavelength of light emitted in the visible region by He⁺ ions after collisions with H atoms is

Q. 43	The ratio of the kinetic energy of the n = 2 electron for the H atom to that of He⁺ ion is

	1.

	2.

	3.	1

	4.	2

	Paragraph for Question Nos. 44 to 46 A small block of mass M moves on a frictionless surface of an inclined plane, as shown in figure. The angle of the incline suddenly changes from 60^o to 30^o at point B. The block is initially at rest at A. Assume that collisions between the block and the incline are totally inelastic (g = 10 m/s²) Ques. The speed of the block at point B immediately after it strikes the second incline is

	1.

	2.

	3.

	4.

Q) A spaceship is launched into a circular orbit close to the earth's surface. what additional velocity should now be imparted to the spaceship in the orbit to overcome the gravitational pull?? ((radius of earth=6400km, g=9.8m/sec^{2 ₎}

	Two lines represented by the equation x² - y² - 2x + 1 = 0 are rotated about the point (1, 0), the line making the bigger angle with the positive directionof the x-axis being turned by 45^o in the clockwise sense and the other line being turned by 15^o in the anticlockwise sense. The combined equation of the pair of lines in their new position is

	1.

	2.

	3.

	4.	none of these

whats the concept of a rotating+translating body??
what are the apt conditions for a rolling body on a horizontal surface to slip off.??

pleez help me out friendzzz!! im a bit weak in physics!!