Official NEET UG 2012 (D1)

Electron in hydrogen atom first jumps from third excited state to second excited state and then from second excited to the first excited state. The ratio of the wavelength \(\lambda  _1: \lambda  _2\) emitted in the two cases is

When a string is divided into three segments of length \(l_1, l_2\) \(l_3 \) the fundamental frequencies of these three segments are \(v_1 , v_2 \) and \(v_3\) respectively. The original fundamental frequency (v) of the string is

A 200 W sodium street lamp emits yellow light of wavelength 0.6 \(\mu \)m. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is.

Two ideal diodes are connected to a battery as shown in the circuit. The current supplied by the battery is :

When a mass is rotating in a plane about a fixed point, its angular momentum is directed along :

An electric dipole of moment ‘p’ is placed in an electric field of intensity ‘E’. The dipole acquires a position such that the axis of the dipole makes an angle \(\Theta \) with the direction of the field. Assuming that the potential energy of the dipole to be zero when \(\Theta \)  = 90\(^o\) , the torque and the potential energy of the dipole will respectively be :

In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2k \(\Omega  \) is 2V. If the base resistance is 1k\(\Omega  \) and the current amplification of the transistor is 100, the input signal voltage is :

A coil of resistance 400\(\Omega  \)is placed in a magnetic field. If the magnetic flux \(\phi \) (wb) linked with the coil varies with time t (sec) as \(\phi \) = 50t\(^2\) + 4. The current in the coil at t = 2 sec is :

A thermodynamic system is taken through the cycle ABCD as shown in figure. Heat rejected by the gas during the cycle is :

If the nuclear radius of \(^{27}\) Al is 3.6 Fermi, the approximate nuclear radius of \(^{64}\) Cu in Fermi is :

Two similar coils of radius R are lying concentrically with their planes at right angles to each other. The currents flowing in them are I an 2 I, respectively. The resultant magnetic field induction at the centre will be:

The potential energy of particle in a force field is ,\(U = \frac{A}{r^2} – \frac{B}{r}. \)  where A and B are positive constants and r si the distance of particle from the centre of the field. For stable equilibrium, the distance of the particle is

When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass . This implies that the liquid must have refractive index.

The horizontal range and the maximum height of a projectile are equal. The angle of projection of the projec- tiles is :

In an electrical circuit R,L, C and an a.c. voltage source are all connected in series. When L is removed from the circuit, the phase difference between the voltage the current in the circuit is \(\pi \)/3. If instead, C is removed from the circuit, the phase difference is again \(\pi \)/3. The power factor of the circuit is :

If the radius of a star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is Q ?

The current (I) in the inductance is varying with time according to the plot shown in figure.

Which one of the following is the correct variation of voltage with time in the coil ?

A milli voltmeter of 25 milli volt range is to be converted into an ammeter of 25 ampere range. The value (in ohm) of necessary shunt will be :

Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat. The length of the boat is 3.0 m and weighs 100 kg. The 55 kg man walks up to the 65 kg man and sits with him. If the boat is in still water the centre of mass of the system shifts by :

A mixture consists of two radioactive materials A\(_1\) and A\(_2\) with half lives of 20s and 10 s respectively. Initially the mixture has 40 g of A\(_1\) and 160 g of A\(_2\) . The amount of the two in the mixture will become equal after :

C and Si both have same lattice structure, having 4 bonding electrons in each. However, C is insulator where as Si is intrinsic semiconductor. This is because :

The height at which the weight of a body becomes 1/16\(^{th}\), its weight on the surface of earth (radius R), is :

An electron of a stationary hydrogen atom passes from the fifth energy level to the ground level. The velocity that the atom acquired as a result of photon emission will be :

(m is the mass of the electron, R, Rydberg constant and h Planckís constant)

A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It :

Four point charges ñQ, ñq, 2q and 2Q are placed, one at each corner of the square. The relation between Q and q for which the potential at the centre of the square is zero is

A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless road. If the banking angle is 45\(^o\), the speed of the car is

A solid cylinder of mass 3 kg is rolling on a horizontal surface with velocity 4ms\(^{-1}\) . It collides with a horizontal spring of force constant 200 Nm\(^{-1}\)  The maximum compression produced in the spring will be :

One mole of an ideal gas goes from an initial state A to final state B via two processes : It first undergoes isothermal expansion from volume V to 3V and then its volume is reduced from 3V to V at constant pressure. The correct P-V diagram representing the two processes is :

Two spheres A and B of masses m\(_1\) and m\(_2\) respectively collide. A is at rest initially and B is moving with velocity v along x-axis. After collision B has a velocity \(\frac{v}{2}\) in a direction perpendicular to the original direction. The mass A moves after collision in the direction.

Liquid oxygen at 50K is heated to 300 K at constant pressure of 1 atm. The rate of heating is constant. Which one of the following graphs represents the variation of temperature with time ?

An alternating electric field, of frequency ?, is applied across the dees (radius = R) of a cyclotron that is being used to accelerate protons (mass = m). The operating magnetic field (B) used in the cyclotron and the kinetic energy (K) of the proton beam, produced by it, are given by :

A spherical planet has a mass M\(_P\) and diameter D\(_P\) . A particle of mass m falling freely near the surface of this planet will experience an acceleration due to gravity, equal to :

A ray of light is incident at an angle of incidence, i, on one face of prism of angle A (assumed to be small) and emerges normally from the opposite face. If the refractive index of the prism is \(\mu \), the angle of incidence i, is nearly equal to :

The damping force on an oscillator is directly proportional to the velocity. The units of the constant of proportionality are :

A concave mirror of focal length ‘f’\(_1\)  is placed at a distance of ‘d’  from a convex lens of focal length ‘f’\(_2\)  A beam of light coming from infinity and falling on this convex lens – concave mirror combination returns to infinity. The distance ‘d’ must equal :

A geostationary satellite is orbiting the earth at a height of 5R above that surface of the earth, R being the radius of the earth. The time period of another satellite in hours at a height of 2R from the surface of the earth is :

Transfer characteristics [output voltage (V\(_0\)) vs input voltage (V\(_i\))] for a base biased transistor in CE configuration is as shown in the figure. For using transistor as a switch, it is used :

If voltage across a bulb rated 220 Volt – 100 Watt drops by 2.5 % of its rated value, the percentage of the rated value by which the power would decrease is

A particle has initial velocity \((2\vec{i} + 3\vec{j})\) and acceleration \((0.3 \vec{i} + 0.2 \vec{j})\). The magnitude of velocity after 10 seconds will be :

Monochromatic radiation emitted when electron on hydrogen atom jumps from first excited to the ground state irradiates a photosensitive material. The stopping potential is measured to be 3.57 V. The threshold frequency of the materials is :

ABC is an equilateral triangle with O as its centre. \(\hat{F}_1 , \hat{F}_2 \) and \(\hat{F}_3\) represent three forces acting along the sides AB, BC and AC respectively. If the total torque about O is zero the magnitude of\(\hat{F}_3\)  is :

The figure shows a logic circuit with two inputs A and B and the output C. The voltage wave forms across A, B and C are as given. The logic circuit gate is :

What is the flux through a cube of side ‘a’ if a point charge of q is at one of its corner :

An \(\alpha \)-particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of 0.25 Wb/m\(^2\)

The electric field associated with an e.m. wave in vacuum is given by \(\vec{E} = \hat{i}\) 40 cos (kz – 6 ×10\(^8\) t), where E, z and t are in volt/m, meter and seconds respectively. The value of wave vector k is :

Which on of the following statements is false in respect of viability of mamalian sperm ?

Evolution of different species in a given area starting from a point and spreading to other geographical areas is known as :

What is the figure given below showing in particular ?

Motile zygote of Plasmodium occurs in :

In an area where DDT had been used extensively, the population of birds declined significantly because:

The human hind brain comprises three parts, one of which is :

The figure below is the diagrammatic representation of the E.Coli vector pBR 322. Which one of the given options correctly identifies its certain component (s) ?

The common bottle cork is a product of :

Which part of the human ear plays no role in hearing as such but is otherwise very much required ?

The most abundant prokaryotes helpful to humans in making curd from milk and in production of antiboitics are the ones categorised as :

Widal Test is carried out to test :

Which part would be most suitable for raising virus-free plants for micropropagation ?

Whic one of the following is a wrong statment ?

Companion cells are closely associated with :

The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 cm. The focal length of lenses are :

Common cold differs from pneumonia in, that :

Pheretima and its close relatives derive nourishment from :

Removal of RNA polymerase III from nucleoplasm will affect the synthesis of :

A process that makes important difference between C\(_3\) and C\(_4\) plants is

PCR and Restriction Fragment Length Polymorphism are the methods for :

Best defined function of Manganese in green plants is :

Measuring Biochemical Oxygen Demand (BOD) is a method used for :

Which one -of the following is not a part of a transcription unit in DNA ?

A certain road accident patient with unknown blood group needs immediate blood transfusion. His one doctor friend at once offers his blood. What was the blood group of the donor ?

Consumption of which one of the following foods can prevent the kind of blindness associated with vitamin’A’ deficiency ?

The motion of a particle along a straight line is described by equation : x = 8 + 12 t –  t\(^3\) where x is in metre and t in second. The retardation of the particle when its velocity becomes zero, is :

Two sources of sound placed close to each other are emitting progressive waves given by y\(_1\) = 4 sin 600 \(\pi \)t and y\(_2\) = 5 sin 608 \(\pi \)t. An observer located near these two sources of sound will hear :

The maximum amount of electrolytes and water (70 – 80 percent) from the glomerular filtrate is reabsorbed in which part of the nephron ?

pH of a saturated solution of Ba(OH)\(_2\) is 12. The value of solubility product (K\(_{SP}\)) of Ba(OH)2\(_2\) is :

When Cl\(_2\) gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from :

Maximum number of electrons in a subshell with :

I = 3 and n = 4 is :

Which one of the following is an outer orbital complex and exhibits paramagnetic behaviour ?

In a reaction, A + B \(\to \)Product, rate is doubled when the concentration of B is doubled, and rate increases by a factor of 8 when the concentrations of both the reactants (A and B) are doubled, rate law for the reaction can be written as :

In which of the following reactions, standard reaction entropy change (\(\triangle \)S\(^o\)) is positive and standard Gibbís energy change (\(\triangle \) G\(^o\)) decreases sharply with increasing temperature ?

Which one of the following is a mineral of iron ?

In Freundlich Adsorption isotherm, the value of 1/n is :

Equimolar solutions of the following substances were prepared separately. Which one of these wil record the highest pH value ?

Both, autogamy and geitonogamy are prevented in –

Placentation in tomato and lemon is

A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro-hormonal control system ?

Which one of the following is not a gaseous biogeochemical cycle in ecosystem ?

A single strand of nucleic acid tagged with a radioactive molecule is called :

Which one of the following options gives one correct example each of convergent evolution and divergent evolution?

An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is :

Cycas and Adiantum resemble each other in having:

What was the most significant trend in the evolution of modern man (Homo sapiens) from his ancestors ?

Cymose inflorescence is present in :

Ribosomal RNA is actively synthesized in

During gamete formation, the enzyme recombinase participates during

Identify the possible link “A” in the following food chain :

Plant \(\to \)insect – frog \(\to \) “A” \(\to \) Eagle

Phyllode is present in :

Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels?

Monascus purpureus is a yeast used commercially in the production of :

The correct sequence of cell organelles during photorespiration is :

Which one of the following is correctly matched ?

A normal visioned man whose father was colour blind, marries a woman whose father was also colour blind. They have their first child as a daughter. what are the chance that this child would be colour blind ?

Signals for parturition originate from :

A patient brought to a hospital with myocardial infarction is normally immediately given :

Which one of the following is not a property of cancerous cells whereas the remaining three are ?

The gynoecium consists of many free pistils in flowers of

Which one of the following is not a functional unit of an ecosystem

In a normal pregnant woman, the amount of total gonadotropin activity was assessed. The result expected was

Which one of the following areas in India, is a hotspot of biodiversity

Which one of the follwing is a correct statement

Which one of the following does not differ in E.coli and Chlamydomonas

50 mL of each gas A and of gas B takes 150 and 200 seconds respectively for effusing through a pin hole under the similar condition. If molecular mass of gas B is 36, the molecular mass of gas A will be :

The correct set of four quantum numbers for the valence elecron of rubidium atom (Z=37) is :

In which of the following compounds, nitrogen exhibits highest oxidation state ?

Predict the product in the given reaction.

Acetone is treated with excess of ethanol in the presence of hydrochloric acid. The product obtained is :

A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is:

Which one of the following, statements is incorrect about enzyme catalysis ?

In a zero- order reaction for every 10\(^o\) rise of temperature, the rate is doubled. If the temperature is increased from 10\(^o\) C to 100\(^o\) C, the rate of the reaction will become :

Deficiency of vitamin B\(_1\) causes the disease

Among the following compounds the one that is most reactive towards electrophilic nitration is :

Buffer solutions have constant acidity and alkalinity because :

The correct order of decreasing acid strength of trichloroacetic acid (A), trifluoroacetic acid (B), acetic acid (C) and formic acid (D) is :

Which one of the following sets of monosaccharides forms sucrose ?

The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0\(^o\)C is :

Which one of the following pairs is isostructural (i.e. having the same shape and hybridization) ?

Bond order of 1.5 is shown by :

Which one of the following is not a condensation polymer ?

In the following sequence of reactions

Which nomenclature is not according to IUPAC system ?

The number of octahedral void(s) per atom present in a cubic close-packed structure is :

In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with :

Identify the alloy containing a non-metal as a constituent in it.

A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number ?

Which one of the alkali metals, forms only, the normal oxide, M\(_2\)O on heating in air ?

The ease of adsorption of the hydrated alkali metal ions on an ion-exchange resins follows the order :

Which one of the following statements regarding photochemical smog is not correct ?

CH\(_3\)CHO and C\(_6\)H\(_5\)CH\(_2\)CHO can be distinguished chemically by :

Which of the statements is not true ?

Standard enthalpy of vapourisation \( \triangle _{vap}\) H\(^o\) for water at 100\(^o\) C is 40.66 kJ mol\(^{-1}\). The internal energy of vaporisation of water at 100oC (in kJmolñ1) is :

(Assume water vapour to behave like an ideal gas).

Identify the wrong statement in the following :

Which of the following statements is not valid for oxoacids of phosphorus ?

The protecting power of lyophilic colloidal sol is expressed in terms of :

Sulphur trioxide can be obtained by which of the following reaction :

P\(_A \)and P\(_B\) are the vapour pressure of pure liquid components, A and B, respectively of an ideal binary solution. If X\(_A\) represents the mole fraction of component A, the total pressure of the solution will be.

Which of the following acids does not exhibit optical isomerism ?

Which of the following species contains three bond pairs and one lone pair around the central atom ?

The pair of species with the same bond order is :

Which of the following statements is false ?

The cycanobacteria are also referred to as

The test-tube Baby Programme employs which one of the following techniques

Which one of the following is a case of wrong matching

The highest number of species in the world is represented by

In which one of the following options the two examples are correctly matched with their particular type of immunity

Which one of the following is wrong statement

Anxiety and eating spicy food together in an otherwise normal human, may lead to

The Leydig cells found in the human body are the secretory source of

Compared to those of humans, the erythrocytes in frog are

In which one of the following the genus name, its two charcters and its phylum are not correctly matched, whereas the remaining three are correct

What is true about ribosomes

Cirrhosis of liver is caused by the chronic intake of

Which one is a true statement regarding DNA polymerase used in PCR

Which statement is wrong for viruses

Which one of the following is correctly matched

How many plants in the list given below have composite fruits that develop from an inflorescence Walnut, poppy, radish, fig, pineapple, apple, tomato, mulberry

Given below is the diagrammatic representation of one of the categories of small molecular weight organic compounds in the living tissues. Identify the category shown and the one blank component “X” in it.

Which one of the following microbes forms symbiotic association with plants and helps them in their nutrition

The extinct human who lived 1,00,000 to 40,000 years ago, in Europe, Asia and parts of Africa, With short stature, heavy eyebrows, retreating fore haeds, large jaws with heavy teeth, stocky bodies, a lumbering gait and stooped posture was

If one strand of DNA has the nitrogenous base sequence at ATCTG, what would be the complementary RNA strand sequence

Which one of the following pairs of hormones are the examples of those that can easily pass through the cell membrane of the target cell and bind to a receptor inside it (Mostly in the nucleus)

Nuclear mebrane is absent in

Which one is the most abundant protein in the animal world

Which one of the following is common to multicellular fungi, filamentous algae and protonema of mosses

Which one single organism or the pair of organisms is correctly assigned ot its or their named taxonomic group

Even in absence of pollinating agents seed setting is assured in

Yeast is used in the production of

Which one out of A -D given below correctly respresents the structural formula of the basic amino acid

The upright pyramid of number is absent in

What is correct to say about the hormone action in humans

Closed vascular bundles lack

Which one of the following is the correct statement for respiration in human

Removal of introns and joining of exons in a defined order during transcription is called :

F\(_2\) generation in a Mendelian cross showed that both genotypic and phenotypic ratios are same as 1 : 2 : 1. It represents a case of :

Given below is the representation of a certain event at a particular stage of a type of cell division. Which is this stage ?