The self-inductance of the motor of an electric fan is 10 H. In order to impart maximum power to the motor at 50 Hz, it should be connected to a capacitance of
Condition for maximum power transfer:
Maximum power transfer takes place at resonant frequency,
An electron and a proton have the same wave length. Which one of the following statements is correct about them?
Two ions of the same charge and energy but different mass are passing through a uniform magnetic field. The radii of their paths are proportional to
A particle of mass m is executing uniform circular motion on a path of radius r. If p is the magnitude of its linear momentum. The radial force acting on the particle is
The resistance of a conductor increases with
The potential difference between two electrodes of a galvanic cell, in an open circuit, is known as
An electron remains undeflected when passing perpendicular to mutually perpendicular electric and magnetic fields. If the magnetic field is 8 Gauss and elecric field is 4000 V/m, the velocity of the electron is
Which of the following is deflected by electric field ?
When ultraviolet rays are incident on a metal plate, then the photoelectric effect does not occurs. It occurs by the incidence of
When wavelength of incident photon is decreased upon
If work function of metal is 3 eV then threshold wavelength will be
In an A.C. circuit, a resistance of R Ω is connected in series with an inductance L. If phase angle between voltage and current is 45°, the value of inductive reactance will be
Which of the following rays are not electromagnetic wave?
What is the cause of "Green house effect"?
The electric field inside a charged conductor of radius r is
A 2μF condenser is charged to 500V and then its plates are joined through of consistance. The heat produced in the resistance in joules is
The orbital velocity of an artificial satellite in a circular orbit just above the earth's surface is V. For a satellite orbiting at an altitude of half of the earth's radius, the orbital velocity is
Two metal rods A and B of equal lengths and equal cross sectional areas are joined end to end. The coefficients of thermal conductivities of A and B are in the ratio 2:3 when the free end of A is maintained at 100°C and the free end of B is maintained at 0°C, the temprature of the junciton is
As the rods A and B are connected in series Q/t = constant
Let the temperature of the junction be ‘t’ under thermal equilibrium
The average kinetic energy of a gas molecules at 27°C is 6.21x1021 J. Its average kinetic energy at 227°C will be
A cyclotron oscillator frequency is 10 MHz. If radius of its dees 60 cm, then magnetic field for accelerating the protons is (Given e = 1.6 x 10-19C, mp = 1.67 x 10-27 kg)
v = 10 MHz = 10 x 106 Hz = 107 Hz
R = rm = 60 cm = 0.6 m
e = 1.6 x 10-19 C
m = 1.67 x 10-27 kg
resonance v = Be 2πm
or B = 2πmv e
= 2 x 3.14 x 1.67 x 10 − 27 x 10 7 1.6 x 10 − 19
= 0.66 tesla
A block has been placed on an inclined plane with the slope angle θ, block slides down the plane at constant speed. The coefficient of kinetic friction is equal to
A magnet of magnetic moment M is cut into two equal parts. The two parts are placed perpendicular to each other so that their north poles touch each other. The resultant magnetic moment is
Magnetic moment of each part = m/2
Resultant magnetic moment of perpendicular magnets
Three identical bar magnets are placed in the form of an equilateral triangle with north pole of one touching the south pole of the other as shown in fig. The net magnetic moment of the system is
The force of cohesion is maximum in
Two wires of the same material and length, but diameters in the ratio 1 : 2 are stretched by the same force. The elastic potential energy stored per unit volume for the two wires when stretched, will be in the ratio of
If 200 Mev energy is released in the fission of a single nucleus of 92 U 235 , how many fissions must occur per second to produce a power of 1 kW?
Let n be number of fissions per second.
Each fission produces 200 MeV.
n×200×106 eV is produced in one second by n fissions
But 1 eV =1.6×10−19 J
Hence, power produced =n×200×106×1.6×10−19 Joule per second.
Also 1 J/s = 1 W and
1000 J/s = 1 kW.
The required power is 1 kW.
Why high temperature is required for fusion reaction?
α- particle is equivalent to
The potential energy of a particle executing simple harmonic motion at a distance y from its equilibrium position is
According to the modern theory for nature of light, the light has
Red light is used as danger signal because it is
A person measures the time period of a simple pendulum inside a stationary lift and finds it to beT. If the lift starts accelerating upward with an acceleration of g/3, the time period of pendulum will be
A 2 kg mass is rotating on a circular path of radius 0.8 m with angular velocity of 44 rad-s⁻1. If radius of the path becomes 1 m, then value of angular velocity will be
m1 = 2 kg, r1 = 0.8 m and ω1 = 44m/s
m2 = 2 kg, r2 = 1 m and ω2 = ?
Since there is no external force acting, angular momentum remains conserved.
Therefore, m1ω1r12 = m2ω2r22
44×(0.8)2 = ω2 × (1)2
ω2 = 28.16 rad/sec
The solar system is an example of
In p-n junction, avalanche current flows in circuit when biasing is
If nearly 105 coulomb liberate 1 gm equivalent of aluminium, then the amount of aluminium (equivalent weight 9) deposited through electrolysis in 20 minutes by a current of 50 amp will be
In a semiconductor
At 0K, there are no excitations among the electrons so there are no free electrons in semiconductors at 0K.
When a Van der Waals' gas undergoes free expansion then its temperature
A certain mass of gas at N.T.P. is suddenly expanded three times its volume under adiabatic conditions. The resulting temperature will be (Take γ=1.4)
Which of the following is a dimensionless quantity?
A tuning fork produces wave in medium. If the temperature of the medium changes then which of following will change
Two identical flutes produce fundamental notes of frequency 300 Hz at 27°C. If the temperature of air in one flute is increased to 31°C, the number of the beats heard per second will be
It is easier to draw up a wooden block along an inclines plane than have it up vertically, principally because
The potential energy of a body is given by : A-B x2 (where x is the displacement). The magnitude of force acting on the particle is
A bomb of 12 kg divides in two parts whose ratio of masses is 1 : 3. If the kinetic energy of smaller part is 216 J, then momentum of bigger part in kg-m/s will be
Which of the following is most acidic?
Reductive ozonolysis of benzene produces
The iso-electronic pair is
The energy of a hydrogen atom in its ground state is -13.6eV. The energy of the level corresponding to the energy level equal to 5 is
The alkyl halide is converted into ethyl alcohol by
The chemical change in DNA molecule that could lead to synthesis of protein with an altered amino acid sequence is called
Which of the following compound acts both nucleophile as well as an electrophile?
In the above sequence of reactions, A and B are
Pairs of species having identical shapes for molecules is
The maximum number of hydrogen bonds formed by a water molecule in ice, is
Which of the following does not represent the criterion of spontaneity ?
C(s) + O₂(g) → CO₂(g); ∆H = - 395 KJ
S(s) + O₂(g) → SO₂(g); ∆H = -295 KJ
CS₂(l) + 3O₂(g) → CO₂(g) + 2SO₂(g); ∆H + -1110 KJ
The heat of formation of CS₂ is
The values of Kp1 and Kp2 for the reactions
are in the ratio of 9:1. If degree of dissociation of X and A be equal, then total pressure at equilibrium (1) and (2) are in the ratio:
Half life of a reaction is found to be inversely proportional to the cube of initial concentration. The order of reaction is
A system is said to be in thermodynamic equilibrium when it is in
In which one the following reactions does the heat change represents the heat of formation of water
Methyl orange is an example of which of the following type of dye?
The IUPAC name of the compound having the formula (CH₃)₃C-CH =CH₂ is
In which of the following pairs, both the complexes show optical isomerism?
Which one of the following is expected to exhibit optical isomerism? (en = ethylenediamine)
If hydrogen electrode dipped into solution of pH = 3 and pH = 6 and salt bridge is connected the e.m.f. of resulting cell is
The quantity of electricity required to liberate 112 cm3 of hydrogen at STP from acidified water is
The major cause of air pollution in big cities is
In an electrolytic cell, the flow of electrons is from
When an aqueous solution of sodium chloride is electrolysed using platinum electrodes, the ions discharged at the electrons are
If 0.44 g of a colourless oxide of nitrogen occupies 224 ml at 1520 mm hg and 273°C, then the compound is
Main process for the manufacture of sodium carbonate is
Pressure of a gas is due to
The composition of the common glass is
Iodine is formed when KI reacts with a solution of
The Ksp of CuS,Ag₂S and HgS are 10⁻31, 10⁻44, 10⁻54 respectively. The solubility of these sulphides are in the order
Which is most basic ?
Which one of the following compound is not a protonic acid?
B(OH)3 in aqueous medium coordinates a molecule of water to form the hydrated species
In this species, B3+ ion, because of its small size, exercises a high polarizing power thereby pulling the sigma electron charge of the coordinated O atom towards itself. The coordinated oxygen, in turn, pulls the sigma electron charge of the OH bond of the attached water molecule towards itself. This facilitates the removal of H+ ion from the O - H bond.
Thus, the solution of B(OH)3 in water acts as a weak acid, and it is not a protonic acid.
Which is not observed in nucleophilic addition reaction?
Bakelite is prepared by the reaction between
Ethynic hydrogen is released most easily in :
In Kjeldahl's method ,nitrogen present is estimated as
C₂H₆(g) + nO₂ → CO₂ (g) + H₂O (l) In this equation, the ratio of the coefficients of Co₂ and H₂O is
An organic compound with C = 40% and H = 6.7% will have the empirical formula
A 5% of solution of cane sugar (MW = 342) is isotonic with 1% solution of substance X. The molecular weight of X is
Colloidal solution commonly used in the treatment of eye disease is
Because of larger surface area in collidal state , adsorption in more , also it acts as germ-killer .
0.01 M solution each of urea, common salt and Na₂SO₄ are taken, the ratio of depression of freezing point is
An atom with atomic number 21 belongs to the category of
The weight of pure NaOH required to prepare 250 cm3 of 0.1 N solution is
Which one of the following has the least magnetic moment?
Chromosome present in prolonged prophase in the salivary gland of Drosophila are
Diatoms deposits are called
Which is not a true amphibian animal
Number of peristome teeth in the capsule of Funaria is
A tissue made of thin-walled rectangular cells which takes part in making girth of stem or root is
In which one of the following the spore mother cells and elater mother cells belong to the same cell generation
Who proposed the concept of unit membrane for tripartite structure of lipoproteins?
In mongolism, the patient has
Haemophilia does not occur in women
Membranous tubules that synthesize testosterone are in
When does pairing/synapsis occur in meiosis?
Name the correct order of relative size
The stem cells that give rise to all red blood cells, white blood cells, and platelets are known as:
Stem cells in the red bone marrow called hemocytoblasts give rise to all of the formed elements in blood i.e, RBCs, WBCs and platelets. If a hemocytoblast commits to becoming a cell called a proerythroblast, it will develop into a new red blood cell. The formation of a red blood cell from hemocytoblast takes about 2 days.
Which one of the following correctly matches a Sexually Transmitted Disease (STD) with its pathogen ?
Basophils, eosinophils, and neutrophils are all:
In IVF technique, fusion of ovum and sperm occurs in :
Which is the correct sequence of arrangement of types of WBC in decreasing order in terms of number per mm3 of human blood?
Which of the following is not a phase of hemostasis?
This is a method of birth control :
Which one of the following is not a function of liver?
The most favoured habitat of a plant is called
Two glands that are responsible for secreting protein-digesting enzymes are
Which of the following ecosystem has the highest primary productivity?
Zona glomerulosa or glomerular area of adrenal cortex is involved in
In Pinus, male cone bears a large number of
Combination of apoenzyme and coenzyme produces
Which of these is correct statement ?
Enzyme hexokinase is inhibited by excess glucose 6-P. It is
Modern Man differs from apes in
Implantation of fertilised egg or young embryo occurs under the influence of
Lens and retina of vertebrate eyes are developed from
Mirabilis jalapa exhibits
The cross used to test whether an individual is homozygous (pure) or heterozygous (hybrid) is called
Mendel enunciated principles of inheritance:
Inflammatory response in allergy is due to release by mast cells of
A vaccine is a biological preparation that provides active acquired immunity to a particular infectious disease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins.
Artificially acquired active immunity can be induced by a vaccine, a substance that contains antigen. A vaccine stimulates a primary response against the antigen without causing symptoms of the disease.
R-gene present on plasmid is meant for
True coelom is covered by
Glycoproteins formed in response to viral infections are
What is true about T-lymphocytes in mammals?
Snakes do not have
The organism used for fermentation of lactic acid is
Streptomycin is produced by
Nitrogen fixing enzyme found in root nodules is
Plants deficient in zinc, show reduced biosynthesis of growth hormone
The most essential fatty acid is
Who discovered an alternate pathway of carbon dioxide fixation and is called C₄-pathway ?
The famale cockroach can be distinguished from the male by
Monotrapa is an example of
Chloragogen cells of Earthworm take part in
In which of the following plants does the stem perform the function of storage and perennation?
In earthworm setae occur in all segments except
Main excretory waste product in cockroach is
If a dry fruit is developed from becarpellary ,syncarpous inferior ovary with a single basally placed ovuale,the fruit would be called as
Ao layer of the soil is made of
DNA finger printing technique was first developed by
Electric organs occur in :
Which of the components of the nervous system has both autonomic and somatic divisions?
Aquatic plants generally have a
Edible part of cauliflower is
When yeast ferments glucose, the products are
The cultivation of rice in India was originated in
Some blue green algae can be used as biofertilisers because
What does Bt stand for popular crop of Bt cotton
When a natural predator (living being) is applied on some other organism to control them, this process is called
Which of the following organisms is used as an indicator of water quality?
The function of vessels /xylem is to
The first hormone artifically produced by culturing bacteria is
Which statement in regard to Taenia saginata is true?
Conductivity part of phloem according to Haberlandt (1914) is
Which one of the following is not pollutant?
Biotic potential is increase in population under
Green-house effect refers to
The aleurone layer in maize grain is specially rich in
Killing an organism for feeding is
The wing in Pinus seed is derived from
Which of the following are the most diversed molecules in the cell ?
Which part of a mature sperm contains mitochondria?
What is correct when chromosomes number in leaf cells of an angiosperms is 22?
Which of the following hormones does not promote homeostasis?
Device for self pollination is