A spring of force constant k is cut into lengths of ratio 1: 2 : 3. They are connected in series and the new force constant is k'. Then they are connected in parallel and force constant is k''. Then k' : k'' is
The ratio of resolving powers of an optical microscope for two wave lengths λ1 = 4000 Å and λ2 = 6000 Å is :-
The two nearest harmonics of a tube closed at one end and open at other end are 220 Hz and 260 Hz. What is the fundamental frequency of the system?
Difference between any two consecutive frequencies
So fundamental frequency = 20 Hz
Consider a drop of rain water having mass 1 g falling from a height of 1 km. It hits the ground with a speed of 50 m/s. Take 'g' constant with a value 10 m/s2. The work done by the
(i) gravitational force and the
(ii) resistive force of air is :-
A physical quantity of the dimensions of length that can be formed out of is velocityof light, G is universal constant of gravitation and e is charge] :-
Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are K1 and K2. The thermal conductivity of the composite rod will be :-
A capacitor is charged by a battery. The battery isremoved and another identical uncharged capacitoris connected in parallel. The total electrostaticenergy of resulting system :-
Decreases by a factor of 2
Charge on capacitor
q = CV
when it is connected with another uncharged capacitor.
In a common emitter transistor amplifier the audio signal voltage across the collector is 3V. The resistance of collector is 3 kΩ. If current gain is 100 and the base resistance is 2 kΩ, the voltage and power gain of the amplifier is :-
Thermodynamic processes are indicated in the following diagram :
Process (1) → volume constant → Isochroic
Process (2) → adiabatic
Process (3) → Temperature constant → Isothermal
Process (4) → Pressure constant → Isobaric
Suppose the charge of a proton and an electrondiffer slightly. One of them is – e, the other is(e + De). If the net of electrostatic force and gravitational force between two hydrogen atoms placed at a distance d (much greater than atomicsize) apart is zero, then De is of the order of[Given mass of hydrogen mh = 1.67 × 10–27 kg]
we know, a hydrogen atom has one electron and one proton
so, net charge on each hydrogen atom = (e + ∆e - e) = ∆e
so, electrostatic force ,
where Mh denotes mass of hydrogen
a/c to question,
gravitational force = electrostatic force
we know, K = 9 × 109 Nm²/C², G = 6.67 × 10-11 Nm²/Kg² , Mh = 1.67 × 10-27 Kg
so, 9 × 109 × ∆e² = 6.67 × 10-11 × (1.67 × 10-27)²
or, ∆e² = 6.67 × 10-11 × 1.67 × 1.67 × 10-54/9 × 109
or, ∆e = 1.43767 × 10-37 C
The resistance of a wire is 'R' ohm. If it is meltedand stretched to 'n' times its original length, its newresistance will be :-
The given electrical network is equivalent to :
The de-Broglie wavelength of a neutron in thermalequilibrium with heavy water at a temperature T(Kelvin) and mass m, is :-
Kinetic energy of thermal neutron with equilibrium
Which one of the following represents forward bias diode ?
A long solenoid of diameter 0.1 m has 2 × 104 turnsper meter. At the centre of the solenoid, a coil of 100 turns and radius 0.01 m is placed with its axiscoinciding with the solenoid axis. The current in thesolenoid reduces at a constant rate to 0A from 4 A in 0.05 s. If the resistance of the coil is 10π2Ω.the total charge flowing through the coil during thistime is :-
Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time t1. On other days, if she remains stationary on the moving escalator, then the escalator takes her up in time t2. The time taken by her to walk up on the moving escalator will be
As we learnt in
Case of Relative velocity -
When A & B are moving along with straight line in opposite direction.
Relative velocity of A with respect to B is.
Young's double slit experment is first performed inair and then in a medium other than air. It is foundthat 8th bright fringe in the medium lies where 5th dark fringe lies in air. The refractive index of themedium is nearly :-
Fringe Width in a medium -
- where in
Since wavelength in a medium become
Fringe width in air
Fringe width in any other medium
According to question
A beam of light from a source L is incident normallyon a plane mirror fixed at a certain distance x fromthe source. The beam is reflected back as a spoton a scale placed just above the source I. When themirror is rotated through a small angle q, the spotof the light is found to move through a distance yon the scale. The angle q is given by :-
If θ1 and θ2 be the apparent angles of dip observedin two vertical planes at right angles to each other,then the true angle of dip θ is given by :-
Two cars moving in opposite directions approach each other with speed of 22 m/s and 16.5 m/s respectively. The driver of the first car blows a horn having a a frequency 400 Hz. The frequency heard by the driver of the second car is [velocity of sound 340 m/s] :-
Two blocks A and B of masses 3 m and mrespectively are connected by a massless andinextensible string. The whole system is suspendedby a massless spring as shown in figure. Themagnitudes of acceleration of A and B immediatelyafter the string is cut, are respectively :-
A thin prism having refracting angle 10° is made of glass of refractive index 1.42. This prism is combined with another thin prism of glass ofrefractive index 1.7. This combination produces dispersion without deviation. The refracting angleof second prism should be :-
(μ -1)A + (μ'-1)A = 0
(1.42 -1)x10° = (1.7 -1)A'
4.2 = 0.7A'
A' = 6°
The acceleration due to gravity at a height 1 km above the earth is the same as at a depth d below the surface of earth. Then:-
A potentiometer is an accurate and versatile device to make electrical measurements of E.M.F. because the method involves :-
In zero deflection condition, potentiometer draws
A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be :-
Figure shows a circuit that contains three identicalresistors with resistance R = 9.0 Ω each, two identical inductors with inductance L = 2.0 m Heach, and an ideal battery with emf ε = 18 V. Thecurrent 'i' through the battery just after the switch closed is,...... :-
Radioactive material 'A' has decay constant '8 λ' andmaterial 'B' has decay constant 'λ'. Initially they havesame number of nuclei. After what time, the ratioof number of nuclei of material 'B' to that 'A' will be 1/e?
The diagrams below show regions of equipotentials:-
A positive charge is moved from A to B in each diagram.
W = qΔV
as ΔV is same in all conditions, work will be same.
Two astronauts are floating in gravitational free space after having lost contact with their spaceship.The two will :-
In the space, the external gravity is absent, but there will be a very small gravitational force between the astronauts, due to which both will move towards earth other with a very small acceleration. So, the best correct answer should be (a).
The x and y coordinates of the particle at any timeare x = 5t 2t2 and y = 10t respectively, wherex and y are in meters and t in seconds. Theacceleration of the particle at t = 2s is :-
One end of string of length l is connected to aparticle of mass 'm' and the other end is connectedto a small peg on a smooth horizontal table. If theparticle moves in circle with speed 'v' the net forceon the particle (directed towards centre) will be (T represents the tension in the string) :-
Net force on the particle in uniform circular motion is centripetal force, which is provided by the tension in string.
A particle executes linear simple harmonic motion with an amplitude of 3 cm. When the particle is at 2 cm from the mean position, the magnitude of its velocity is equal to that of its acceleration. Then its time period in seconds is :-
Two Polaroids P1 and P2 are placed with their axisperpendicular to each other. Unpolarised light I0 isincident on P1 . A third polaroid P3 is kept in betweenP1 and P2 such that its axis makes an angle 45° withthat of P1 . The intensity of transmitted light throughP2 is :-
The bulk modulus of a spherical object is 'B'. If itis subjected to uniform pressure 'p', the fractional decrease in radius is:-
In an electromagnetic wave in free space the root meansquare value of the electric field is Erms = 6V/m. Thepeak value of the magnetic field is :-
A rope is wound around a hollow cylinder of mass3 kg and radius 40 cm. What is the angularacceleration of the cylinder if the rope is pulled witha force of 30 N ?
Two discs of same moment of inertia rotating about their regular axis passing through centre and perpendicular to the plane of disc with angular velocities ω1 and ω2 . They are brought into contact face to face coinciding the axis of rotation. The expression for loss of energy during this process is:-
The photoelectric threshold wavelength of silver is3250 × 10–10m. The velocity of the electron ejected from a silver surface by ultraviolet light ofwavelength 2536 × 10–10 m is :-
(Given h = 4.14 × 10–15 eVs and c = 3 × 108 ms–1)
A 250-Turn rectangular coil of length 2.1 cm andwidth 1.25 cm carries a current of 85 µA and subjectedto magnetic field of strength 0.85 T. Work done forrotating the coil by 180º against the torque is:-
W = MB (cosθ1– cosθ2)
When it is rotated by angle 180º then
W = 2MB
W = 2 (NIA)B
= 2 x 250 x 85 x 10-6[1.25 x 2.1 x 10-4] x 85 x 10-2
The ratio of wavelengths of the last line of Balmerseries and the last line of Lyman series is :-
A carnot engine having an efficiency of 1/10 as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is :-
A gas mixture consists of 2 moles of O2 and 4 molesof Ar at temperature T. Neglecting all vibrationalmodes, the total internal energy of the system is :-
An arrangement of three parallel straight wires placed perpendicular to plane of paper carrying
same current 'I along the same direction is shown in fig. Magnitude of force per unit length on the middle wire 'B' is given by :-
A U tube with both ends open to the atmosphere, is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of 10 mm above the water level on the other side. Meanwhile the water rises by 65 mm from its original level (see diagram). The density of the oil is :-
Which of the following statements are correct ?
(a) Centre of mass of a body always coincides with the centre of gravity of the body
(b) Central of mass of a body is the point at which the total gravitational torque on the body is zero
(c) A couple on a body produce both translational and rotation motion in a body
(d) Mechanical advantage greater than one means that small effort can be used to lift a large load
Centre of mass may lie on centre of gravity net torque of gravitational pull is zero about centre of mass.
Name the gas that can readily decolourise acidified KMnO4 solution :
Mechanism of a hypothetical reaction
The element Z = 114 has been discovered recently.It will belong to which of the following family/groupand electronic configuration ?
The heating of phenylmethyl ethers with HIproduces
Which one is the correct order of acidity ?
Acidic strength ∝ Electronegativity of Carbon ∝ % s−character
Correct order of acidic strength
Predict the correct intermediate and product in the following reaction :
The equilibrium constant of the following are :
Which one is the most acidic compound ?
The correct increasing order of basic strength for the following compounds is :
Ionic mobility of which of the following alkali metalions is lowest when aqueous solution of their saltsare put under an electric field ?
The most suitable method of separation of 1 : 1mixture of ortho and para-nitrophenols is :
The ortho and para isomers can be separated by steam distillation o-Nitrophenol is steam volatile due
to intramolecular hydrogen bonding while p-nitro phenol is less volatile due to intermolecular hydrogen bonding which cause association of
HgCl2 and I2 both when dissolved in water containing I ions the pair of species formed is :
Mixture of chloroxylenol and terpineol acts as :
An example of a sigma bonded organometallic compound is :
Grignard's reagent i.e., RMgX is σ-bonded organometallic compound.
A first order reaction has a specific reaction rateof 102 sec1. How much time will it take for 20gof the reactant to reduce to 5 g ?
Match the interhalogen compounds of column-I with the geometry in column II and assign the
Concentration of the Ag+ ions in a saturated solution of Ag2C2O4 is 2.2 × 104 mol L1 Solubility product of Ag2C2O4 is :-
Which of the following pairs of compounds isisoelectronic and isostructural ?
Total number of valence electrons are equal in both the species and both the species exhibit linear shape.
The IUPAC name of the compound
The process of heating the concentrated ore in a limited supply of air or in the absence of air is known as:
In the process of metallurgy, Calcination is used for the concentration of ore to oxide. It is a process of heating an ore in a limited supply of air. If the ore is heated in the presence of excess of air then its ia known as roasting. Generally carbonate ores are calcined and hence carbon dioxide is given out.
Which is the incorrect statement ?
In frenkel defect the radius of cation must be very less than anion. Incorrect statement is (3)
The species, having bond angles of 120° is :-
For a given reaction, ΔH = 35.5 kJ mol1 and ΔS = 83.6 JK1mol1. The reaction is spontaneous at : (Assume that ΔH and ΔS do not vary with tempearature)
Which of the following is a sink for CO ?
Microorganism present in the soil.
If molality of the dilute solutions is doubled, the valueof molal depression constant (Kf) will be :-
Kf does not depend on concentration of solution. It only depends on nature of solvent so it will be unchanged. option (3)
Which of the following is dependent ontemperature?
Temperature dependent unit is molarity.
Which one of the following statements is notcorrect?
Equilibrium constant is not affected by presence of catalyst hence statement (1) is incorrect.
Identify A and predict the type of reaction
The correct order of the stoichiometries ofAgCl formed when AgNO3 in excess is treated with the complexes : CoCl3.6NH3, CoCl3.5NH3,CoCl3.4NH3 respectively is :-
The correct statement regarding electrophile is :-
Electrophile can be either neutral or positively charged species and can form a bond by accepting a pair of electron from a nucleophile.
A gas is allowed to expand in a well insulatedcontainer against a constant external pressure of2.5atm from an initial volume of 2.50 L to a finalvolume of 4.50L. The change in internal energyΔU of the gas in joules will be:-
Which of the following reactions is appropriate forconverting acetamide to methanamine ?
This reaction is known as hoffmann
With respect to the conformers of ethane, whichof the following statements is true ?
In conformation bond angle and bond length
In which pair of ions both the species contain SS bond?
It is because of inability of ns2 electrons of the valence shell to participate in bonding that:-
Correct increasing order for the wavelengths of absorption in the visible region the complexes of Co3+ is :-
Consider the reactions :-
Of the following, which is the product formed when cyclohexanone undergoes aldol condensation followed by heating ?:-
Which of the following pairs of species have thesame bond order ?
Total no. of electrons in CN– is 14
Total no. of electrons in CO is also 14
hence B.O. of both CN– & CO is 3
Extraction of gold and silver involes leaching with CNion. Silver is later recovered by :-
A 20 litre container at 400 K contains CO2(g) atpressure 0.4 atm and an excess of SrO (neglectthe volume of solid SrO). The volume of thecontainer is now decreased by moving the movablepiston fitted in the container. The maximum volumeof the container, when pressure of CO2 attains itsmaximum value, will be :-
Pick out the correct statement with respect to[Mn(CN)6]3:-
The reason for greater range of oxidation statesin actinoids is attributed to :-
Minimum energy gap between
5f, 6d & 7s subshell. Thats why e exitation will be easeir.
Which of the following statements is not correct :-
Denaturation makes the protein more active.
Which one of the following statements is correct,with reference to enzymes ?
A decrease in blood pressure / volume will notcause the release of :
Which cells of "Crypts of Lieberkuhn" secreteantibacterial lysozyme ?
Which of the following are not polymeric ?
Functional megaspore in an angiosperm developsinto ?
Chipko movement was launched for the protection of
Myelin sheath is produced by :
Receptor sites for neurotransmitters are present on :
Coconut fruit is a :
Adult human RBCs are enucleated. Which of thefollowing statement(s) is/are most appropriateexplanation for this feature ?
(a) They do not need to reproduce
(b) They are somatic cells
(c) They do not metabolize
(d) All their internal space is available for oxygen transport
Capacitation occurs in :
Which of the following are found in extreme salineconditions ?
Asymptote in a logistic growth curve is obtainedwhen :
Artificial selection to obtain cows yielding higher milk output represents :
Select the mismatch :
Good vision depends on adequate intake of carotene rich food : Select the best option from the following statements :
(a) Vitamin A derivatives are formed from carotene
(b) The photopigments are embedded in the membrane discs of the inner segment
(c) Retinal is a derivative of Vitamin A
(d) Retinal is a light absorbing part of all the visual photopigments Options :
The DNA fragments separated on an agarose gelcan be visualised after staining with :
The hepatic portal vein drains blood to liver from:
The vascular cambium normally gives rise to :
Thalassemia and sickle cell anemia are caused dueto a problem in globin molecule synthesis. Selectthe correct statement :
The genotypes of a husband and Wife are IAIB and IA i. Among the blood types of their children, how manydifferent genotypes and phenotypes are possible?
Which of the following facilitates opening ofstomatal aperture ?
In Bougainvillea thorns are the modifications of :
Which one of the following is related to Ex-situconservation of threatened animals and plants ?
Root hairs develop from the region of :
A disease caused by an autosomal primary non-disjunction is :
The water potential of pure water is :
Which of the following options gives the correctsequence of events during mitosis ?
The process of separation and purification ofexpressed protein before marketing is called :
A temporary endocrine gland in the human bodyis :
Which of the following is made up of dead cells?
An example of colonial alga is :
Match the following sexually transmitted diseases (Column-I) with their causative agent (Column-II) and select the correct option :
The function of copper ions in copper releasingIUD's is :
Which of the following in sewage treatmentremoves suspended solids ?
An important characteristic that Hemichordatesshare with Chordates is :
The final proof for DNA as the genetic materialcame from the experiments of :
Among the following characters, which one wasnot considered by Mendel in his experiments onpea ?
Plants which produce characteristic pneumatophoresand show vivipary belong to :
The pivot joint between atlas and axis is a typeof :
Synovial joints are freely movable joint which allow considerable movements. Pivot joint is a type of synovial joint which provide rotational movement as in between atlas and axis vertebrae of vertebral column
With reference to factors affecting the rate ofphotosynthesis, which of the following statementsis not correct ?
DNA fragments are:
Which of the following components provides stickycharacter to the bacterial cell ?
Which of the following options best represents theenzyme composition of pancreatic juice ?
Which among these is the correct combination ofaquatic mammals ?
Fruit and leaf drop at early stages can be preventedby the application of:
Select the correct route for the passage of spermsin male frogs:
In case of a couple where the male is having a verylow sperm count, which technique will be suitablefor fertilisation ?
Which ecosystem has the maximum biomass ?
Lungs are made up of air-filled sacs, the alveoli.They do not collapse even after forceful expiration,because of:
Presence of plants arranged into well definedvertical layers depending on their height can be seenbest in:
Which of the following statements is correct ?
Alexander Von Humbolt described for the first time:
Zygotic meiosis is characteristic of;
If there are 999 bases in an RNA that codes fora protein with 333 amino acids, and the base atposition 901 is deleted such that the length of theRNA becomes 998 bases, how many codons will bealtered ?
Flowers which have single ovule in the ovary and are packed into inflorescence are usually pollinated by
Transplantation of tissues/organs fails often due tonon-acceptance by the patient's body. Which typeof immune-response is responsible for suchrejections ?
Life cycle of Ectocarpus and Fucus respectively are:
A gene whose expression helps to identifytransformed cell is known as :
A dioecious flowering plant prevents both :
Which statement is wrong for Krebs' cycle ?
Phosphoenol pyruvate (PEP) is the primary CO2 acceptor in:
During DNA replication, Okazaki fragments areused to elongate:
Which of the following RNAs should be mostabundant in animal cell ?
GnRH, a hypothalamic hormone, needed inreproduction, acts on:
What is the criterion for DN A fragments movementon agarose gel during gel electrophoresis ?
Hypersecretion of Growth Hormone in adults doesnot cause further increase in height, because:
DNA replication in bacteria occurs:
Which one from those given below is the periodfor Mendel's hybridization experiments ?
Viroids differ from viruses in having;
MALT constitutes about ________ percent of thelymphoid tissue in human body.
Which of the following is correctly matched for theproduct produced by them ?
Which among the following are the smallest livingcells, known without a definite cell wall, pathogenicto plants as well as animals and can survive withoutoxygen ?
Which of the following represents order of'Horse' ?
Frog's heart when taken out of the body continues to beat for sometime. Select the best option from the following statements.
(a) Frog is a poikilotherm.
(b) Frog does not have any coronary circulation.
(c) Heart is "myogenic" in nature.
(d) Heart is autoexcitable Options:
Homozygous purelines in cattle can be obtained by:
Identify the wrong statement in context ofheartwood:
Anaphase Promoting Complex (APC) is a proteindegradation machinery necessary for proper mitosisof animal cells. If APC is defective in a human cell,which of the following is expected to occur ?
Which of the following cell organelles is responsiblefor extracting energy from carbohydrates to formATP ?
Mycorrhizae are the example of:
Out of 'X' pairs of ribs in humans only 'Y' pairs aretrue ribs. Select the option that correctly representsvalues of X and Y and provides their explanation:
In case of poriferans, the spongocoel is lined withflagellated cells called: