If an 8 Ω resistance and 6 Ω resistance, are present in an a.c. series circuit, then the impedance of the circuit will be
The Hα line is the first member of the Balmer series of the hydrogen spectrum and it occurs due to the transition of the electron from the 3rd orbit to the 2ndorbit. If its wave length is λ , the wave length of the last member of the Balmer series will be
Emission of electrons in the photoelectric effect is possible, if
Sodium has body centred packing. Distance between two nearest atoms is 3.7 Å . The lattice parameter is:
Two inclined plane have same height but different lengths (and therefore different angles). If a solid sphere is allowed to roll down from the top of these inclined planes
What will be the ratio of the de Broglie wavelengths of proton and α particle of same energy ?
In a place where electric field E and magnetic field B are finite, a charged particle projected along x-axis with speed v passes undeflected and with uniform speed. We may conclude that
Correct Answer : c
Explanation : B field is perpendicular to each other such that electric magnetic field and propagation of electromagnetic waves are mutually perpendicular to each that means if that electric field is X and magnetic field is Y then the direction of electromagnetic wave should be Z
Two identical cells of the same emf and same internal resistance give the same current through an external resistance of 2 Ω, regardless of whether they are connected in series or parallel. The internal resistance of the cell is
What is the unit for specific resistivity ?
A photon of energy 4 eV is incident on a metal surface whose work function is 2 eV. Minimum value of reverse potential to be applied for stopping the emission of electrons is
De-Broglie equation states the
Three identical rings move with the same speed on a horizontal surface in a uniform horizontal magnetic field, normal to the planes of the rings. If the first slips without rolling, the second rolls without slipping and the third rolls with slipping with the same speed, then
Heat radiations propagate with the speed of
In an electromagnetic wave, the electric and magnetising fields are 100 Vm-1 and 0.265 Am-1. The maximum energy flow is
S = E0 x H0
E0 = 100 Vm-1, H0 = 0.265 Am-1
∴ S = 100 x 0.26 = 26.5 Wm-2
Two electric charge 12μC and − 6μC are places 20 cm apart in air. There will be a point P at which electric potential is zero on the line joining these two charges and outside, excluding the region between them. The distance of P from − 6 μ C charge is
An electric dipole of dipole moment p is placed in uniform electric field of strength E. If θ is the angle between p and E, then potential energy of the dipole becomes maximum, when θ is
A space-craft is launched in a circular orbit very close to the earth. What additional velocity should be given to the space-craft, so that it might escape from the earth's gravitational pull? (Radius of the earth = 6400 km; g = 9.8 m-s⁻2)
On a cold morning, a metal surface will feel colder to touch than a wooden surface because
Gas exerts pressure on the walls of the container because
Five forces inclined at an angle of 72° to each other are acting on a particle of mass m placed at origin of co-ordinates. Four forces are of magnitude F₁ and one of F₂. Find resulting acceleration of particle
The net charge on a current carrying conductor is
In a deflection magnetometer experiment the deflections produced separately by two short bar magnets kept at the same distance are 45° and 30° . Then the ratio of the magnetic moments of the two magnets is
For deflection magnetometer
A magnetic needle suspended freely orients itself
In streamline flow, if gravitational head is h, then pressure and kinetic heads are
A wire of length L and radius a rigidly fixed at one end. On stretching the other end of the wire with a force F, the increase in it length is l. If another wire of same material but of length 2L and radius 2a is stretched with a force 2F, the increase in its length will be
In a fission of U235 nucleus on average ----- neutrons are released.
When U235 is bombarded by a neutron, it splits into barium,
Krypton and 2 or 3, so average 2.5 neutrons per fission
A heavy nucleus at rest breaks into two fragments which fly off with velocities 8:1. The ratio of radii of the fragments is
A radioactive sample at any instant has its disintegration rate 5000 disintegrations per minute. After 5 min, the rate is 1250 disintegrations per min. Then, the decay constant (per minute) is
A body of mass 2 kg is made to oscillate with an angular frequency 4 rad-s⁻1 on a spring. The force constant of the spring is
Light is incident on a glass plate at an angle of 60°. If reflected and refracted rays are mutually perpendicular, then refractive index of the glass plate is
If the dispersive power of a lens material of focal length 20 cm is 0.08, then longitudinal chromatic aberration of the lens is
If the radius of the earth is suddenly contracts to half of its present value, then the duration of day will be of
In an orbital motion, the angular momentum vector is
A mass m is suspended from a string of length l and force constant K. The frequency of vibration of the mass is f₁. The spring is cut into two equal Parts and the same mass is suspended from one of the parts. The new frequency of vibration of mass is f₂. Which of the following relations between the frequencies is correct
Barrier potential of a P-N junction diode does not depend on
As the temperature of hot junction increases, the thermo emf
The reason of current flow in P-N junction in forward bias is
The amount of heat required to raise the temperature of a body through 1 K is called, its
Two moles of monoatomic ideal gas at 60°C are mixed adiabatically with one mole of another monoatomic ideal gas at 12°C. The final temperature of the mixture is
Dimensions of the following three quantities are the same
The relation between time the displacement for two particles is given by y₁ = 0.06 sin 2π (0.04t + φ₁) and y₂ = 0.03 sin 2π (1.04t + φ₂) The ratio of the intensity of the waves produced by the vibrations of the two particles will be
A transverse wave is represented by the equation y = y₀ sin 2π/λ (νt - x). for what value of λ is the maximum particle velocity equal to two times the wave velocity?
A machine which is 75% efficient, uses 12 joules of energy in lifting up a 1 kg mass through a certain distance. The mass is then allowed to fall through that distance. The velocity at the end of its fall is (in ms⁻1)
given efficiency of the machine is 75% and it is spending 12 J of energy to lift that mass
according to the law of conservation of energy the stored potential energy in the mass will be converted to its kinetic energy. hence,
A particle of mass m at rest is acted upon by a force P for a time t. Its kinetic energy after an interval t is
A body at rest breaks up into 3 parts. If 2 parts having equal masses fly off perpendicularly each after with a velocity of 12 m/s, then the velocity of the third part which has 3 times mass of each part is
The order of reactivity of halogen acids for reaction with C₂H₅OH is
The appropriate reagent for the transformation
With increasing principle quantum number, the energy difference between adjacent energy levels in H atom
Isotopes of an element have different
Which of the following is the strongest nucleophile?
A negatively charged nucleophile is always stronger than a neutral one
Haloalkane in the presence of alcoholic KOH undergoes
The enzymes which convert glucose and fructose into ethyl alcohol is
What is the main reason for the fact that carboxylic acids can undergo ionization?
Which of the following bond has the largest bond length?
The structure of ICl₂⁻ is
For the reaction of mole of zinc dust with one mole of sulphric acid in a bomb calorimeter ,ΔU and w correspond to
The standard molar heat of formation of ethane ,CO₂ and water (l) are respectively -21.0,-94.1 and -68.3 Kcal mol⁻1. The standard molar heat of combustion of ethane will be
The equilibrium between water and its vapour, in an open-vessel
In an open vessel, the water vapour diffuse into air and therefore, the concentration of water vapour above water surface is negligible.
The reverse process of condensation of vapour into liquid form is almost absent.
Therefore, evaporation process continues, till the entire water changes into vapour form.
Therefore, in an open vessel, the water vapour system is never in equilibrium.
Finally the whole water will diffuse into air as water vapour.
If concentration of reactants is increased by 'x' then the k becomes
A Carnot engine receives heat at 227°C and exhausts at 47°C. If its efficiency is to be increased by 5 % then the engine should receive heat at
The heat of neutralisation of strong base and strong acid is -57.0 kJ. The heat released when 0.5 mole of HNO₃ solution is added to 0.20 moles of NaOH solution is
The commonly used antiseptic in cosmetics is
The isomers which can be converted into another form by rotation of molecules around single bond are
Which of the following complexes is an outer orbital complex?
The IUPAC name of K₃[Ir(C₂O₄)₃] is
Two electrolytic cells, one containing acidified ferrous chloride and another acidified ferric chloride, are connected in series. The ratio of iron deposited at cathodes in the two cells will be
The reference electrode is made by using
The equivalent conductance of NaCl,HCl and C₂H₅COONa at infinite dilution are 126.45 , 426.16 and 91 ohm⁻1 cm2 eq-1. The eq.conductance of C₂H₅COOH is
Which of the following is a secondary pollutant?
Which of the following has highest conductivity?
The fomula of calcium chlorite is
If the pressure and absolute temperatre of 2 litres of CO₂ are doubles, the volume of CO₂ would become
A closed flask contains water in all its three states, solid, liquid and vapour at 0°C. In this situation the average kinetic energy of water molecules will be
The average kinetic energy is maximum in the gaseous state
The catenation tendency of C, Si and Ge is in the order Ge<Si<C. The bond energies (in kJ mol⁻1) of C-C, Si-Si and Ge-Ge bonds respectively are
Which one of the following reacts with glass?
When rain is accompanied by thunderstorm, the collected rain water will have a pH value
Sodium carbonate cannot be used in place of ammonium carbonate for the identification of the fifth group radicals . This is because the
The one which is least basic is
Increasing order of pka values (pKa = - log ka) pka of H2O,CH3OH and C6H5OH is :
pka value of H2O is 15.7, C6H5OH is 9.95 and CH3OH is 16 so C6H5OH< H2O <CH3OH
Select incorect statement(s):
The best method for the separation of naphthalene and benzoic acid from their mixture is
Bakelite is prepared from
A liquid decomposes at its normal pressure. It can be purified by
An oxidising agent is a substance which can
Normality of 0.3 M H3PO4 solution is
Normality = molarity x basicity
Now, basicity of H3PO4 = 3
So, Normality = 0.3 x 3 = 0.9
How much water is needed to dilute 10 ml of 10 N hydrochloric acid to make it exactly decinormal (0.1N) ?
When mercuric iodide is added to the aqueous solution of potassium iodide, the
Which of the following electrolytes is least effective in causing flocculation of ferric hydroxide sol?
The nature of an aqueous solution of FeCl₃ is
When (NH₄)₂Cr₂O₇ is heated, the gas evolved is
Gametes formed by meiosis are called
Mucus helps frog in forming
Atactostele is found in
The moss plants develop from
Bryophytes are dependent on water because
Tetrad is made of
A chromosome carrying the centromere, at one of the ends, is called
Which one does not possess RNA ?
If the lysosomes get ruptured in a cell which of the following can happen?
The term 'cell' was coined by
Diethyl sulphate (DES) is
A single recessive allele which can express its effect should occur on
Which of the following anemia types is an example of a genetic disorder?
Compared to blood our lymph has
If you had 10 RBCs each containing 100 molecules of hemoglobin, how many molecules of oxygen could these RBCs transport?
Which mineral is essential for coagulation to occur?
In IVF technique, fusion of ovum and sperm occurs in :
The function of copper-T is to prevent
Ovary is called inferior in
Which of the following is not readily absorbed in the small intestine?
Gastrin secretion will stop when the stomach pH reaches _____.
Loss of relative biological equilibrium is due to
Homeostasis is the term used to describe
Herring bodies are found in
Optimum pH for enzyme trypsin is
Which is not true about inorganic catalysts and enzymes ?
The most nearest prehistoric ancestro of present man may be
Resin glands in Pinus are
Heterospory and polyembryony is found in
If Mendel had studied the 7 traits using a plant with 12 chromosomes instead of 14, in what way would the interpretation have been different ?
Mendelian recombinations are due to
Emasculation is a part of :
The part of eye acting as a diaphragm of camera is
Type of immunoglobulin present in colostrum/mother's milk is
Interferon suppresses the pathogenicity of
Short lived immunity acquird by foetus/infant from mother through placenta/milk is
Most abundant immunoglobulin is
Long hollow bones connected by passages are characteristic of
Female Ascaris is differentiable from male is
A fungus that causes damage to timber resources is
Bacteria possess the organelle
Bacterial endotoxin is
Triglyceride consists of
A crop plant which can grow in nitrogen deficient soil without external supply of it is
Which can function as carrier in active ion absorption
The transfer of minerals from top soil to sub soil through soil water is called
A common feature of trachea of insects and that of mammals is that both
Number of abdominal segments of Cockroach is
Find out hermaphrodite organism.
In earthworm locomotion occurs with the help
Haustorial root is present in
Grass stem elongates by the activity of
Identify the plant in which the leaves of adult plant are phyllodes while the seedling leaves are not reduced
The plant, which bears clinging roots is
Sympathetic nervous system is also called
Hydrophyte with both hydrophytic and xerophytic traits is
Stem of submerged hydrophytes is soft and weak because of
A fish propels itself forward with its
The first hormone artifically produced by culturing bacteria is
Large number of bacteria produced from a single bacterium is called
Bagasse is related to the manufacture of
A new crop which produces long pods with four prominent wings, is
Mule is product of
Sporeine is a/an
Pasteurization is heating at
Microorganisms are grown as a layer or film on the surface of nutrient medium in
Given below are assertion and reason. Point out if both are true with reason being correct explanation (A), both true but reason is not correct explanation (B), assertion true but reason wrong (C), and both wrong (D), Assertion. Vascular cambium is considered as lateral meristem. Reason. It gives rise to lateral shoots
Root hairs develop from
When the missing parts are formed the phenomenon is called
Noniosing radiations with specific biological effects are
The radioactive pollution is caused by
The term 'bio-magnification' refers to the
A bird introduced from another country became a serious pest due to
Which is not a primary coloniser?
Which one is phosphoprotein ?
How many antipodal cells are present in polygonum type embryo sac
An interesting modification of flower shape for insect pollination occurs in some orchids in which a male insect mistakes the pattern on the orchid flower for the female of his species and tries to copulate with it, there by pollinating the flower. This phenomenon is called
Embryosac is also known as
Development of egg without fertilization is called
The function of the endometrium is to
Which of the following store sperm cells and eliminate those that have major genetic defects?
A rise in blood levels of FSH at the beginning of the ovarian cycle causes
The production of testosterone is regulated by
Sugarcane belong to the family-
The presence of epicalyx and Monoadelphous condition of stamens is a characteristic feature of family-