The efficiency of transformer is very high because
An electron is travelling horizontally towards east. A magnetic field is vertically downward direction exerts a force on the electron in the direction of
Given three equal resistors, how many different combination of all the three resistors can be made?
The maximum velocity at the lowest point, so that the string just slack at the highest point in a vertical circle of raidus l
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
A positron and a proton are accelerated by the same accelerating potential. Then the ratio of the associated wavelengths of positron and proton will be [M = mass of proton; m = mass of positron]
Since both proton and positron have the same charge
In photoelectric effect if the intensity of light is doubled then maximum kinetic energy of photoelectrons will become
A wire of length 100 cm is connected to a cell of emf 2 V and negligible internal resistance. The resistance of the wire is 3 Ω. The additional resistance required to produce a pot. diff. Of 1 millivolt per cm is
Correct Answer :- b
Explanation : Voltage drop across wire = 1 X 10-3 X 100
= 0.1 V
Let current in circuit be I
0.1 = 1 * 3 = (3*2)/(R+3)
R = 57Ω
Which of the following electromagnetic waves has minimum frequency ?
The slope of a graph between frequency of light (v) and stopping potential (V₀) is (where h = Planck's constant and c = Charge on an electron)
A photocell stops emission if it is maintained at 2V negative potential. The energy of most energetic photoelectron is
A coil of wire of radius r has 600 turns and a self inductance of 108 mH. The self inductance of a similar coil of 500 turns will be
Which of the following rays has minimum frequency?
The range of wavelength of visible light is
A straight wire of length l and electric dipole moment p is bent to from a semicircle. The new electric dipole moment would be
There is 10 units of charge at the centre of a circle of radius 10m. The work done in moving 1 unit of charge around the circle once is
A body is projected vertically upwards from the surface of a planet of radius R with a velocity equal to half the escape velocity for that planet. The maximum height attained by the body is
Two identical conducting rods are first connected independently to two vessels, one containing water at 100°C and the other containing ice at 0°C. In the second case, the rods are joined end to end and connected to the same vessels. Let Q1 and Q2 be the rates of melting of ice in the two cases respectively. The ratio Q1/Q2 is
In the first case rode are in parallel and thermal resistance is R/2 while in second case rods are in series and thermal resistance is 2R.
A cyclist moving with a speed of 4.9 m−s⁻1 on a level road can take a sharp circular turn. The coefficient of friction between the cycle tyres and road is 0.5, then radius of the turn is
If two moles of diatomic gas and one mole of mono atomic gas are mixed then the ratio of specific heats is
A galvanometer of resistance 98 Ω is shunted by a resistance of 2 Ω . The fraction of total current that passes through the galvanometer is
The material suitable for making electromagnets should have
A magnet is placed with its north pole facing north in north-south direction. In its map of magnetic field the null points will be
Two pieces of a glass plate, placed one upon the other with a little water in between them, can not be separated easily, because of
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
The phenomena in which proton flips is
The nucleus of 56Ba141 contains ---- neutrons
The nature of sun's spectrum is
If a body is released into a tunned dug along the diameter of the earth of radius R₀, it executes the S.H.M. with time period:
The radio - isotope of this element is used in the treatment of cancer
A prism of refracting angle 60° is made with a material of refractive index μ . For certain wave length of light, the angle of minimum deviation is 30° . For this wave length, the value of μ of material is
If the moment of inertia of a wheel, having radius of gyration 60 cm, is 360 kg-m2, then mass of the wheel is
A spherical solid ball of 1 kg mass and radius 3 cm is rotating about an axis passing through its centre with an angular velocity of 50 radian/s. The kinetic energy of rotation is
The motion of a particle excuting S.H.M. is given by x=0.01 sin 100π(t+.05), where x is in metres and time is in seconds. The time period is
Intrinsic germanium cystal is doped with which of the following so as to make it a N-type semiconductor
In p-type semiconductor
Faraday's laws of electrolysis are related to
If m is the mass, θ is temp. and 's' is specific heat, then thermal capacity k is given by
50g of copper is heated to increase its temperature by 10°C. If the same quantity of heat is given to 10gm of water, the rise in temperature is (specific heat of copper = 420J/kg °C, specific heat of water = 4200 J/kg °C)
The path difference between the two waves y₁ = a₁ sin (ωt - 2πx/λ) and y₂ = a₂ cos (ωt - 2πx/λ + φ) is
Who discovered the X-rays?
A motor cycle starts from rest and accelerates along a straight path at 2m/s2. At the starting point of the motor cycle there is a stationary electric siren. How far has the motor cycle gone when the driver hears the frequency of the siren at 94% of its value when the motor cycle was at rest? (Speed of sound = 330ms-1)
When a body of mass 1 kg is attached to a spring of length 50 cm, the spring stretches by 2 cm. The mass is pulled down, until length of the spring becomes 60 cm. The amount of elastic potential energy stored in the spring in this condition is
A bullet of mass 3g initially travelling with a velocity 500 m−s⁻1 penetrates 12 cm into a wooden block. What average force does it exert?
The energy which an e⁻ acquires when accelerated through a potential differnce of 1 volt is called
Glycerol is an alcohol which can be classified as
Schiff's reagent is
How many possible combination of quantum number are there for N shell?
For N-Shell, n = 4.
Maximum no of electrons in 4th shell = 2n2
=2 x 4 x 4
According to Pauli Exclusion Principle, "No to two electrons can have the all four quantum numbers same". Thus the possible combination of quantum numbers = 32
Rutherford's experiment led to the discovery of
The four bonds in methane are directed in space at an angle of
An example of amino acid containing benzene ring is
The compound with carbon uses only its sp3 hybrid orbitals for bond formation is
The fatty acid which shows reducing property is
Which of the following is polar?
Which pair of elements among the following will form most stable ionic bond
Which of the following is the correct arrangement in the increasing order of the enthalpy of vaporisation?
According to third law of thermodyanamics which of the following quantity for a perfectly crystalline solid is zero at absolute zero
In a reversible reaction, the catalyst
The decomposition of a substance follows first order kinetics. If its conc. is reduced to 1/8th of its initial value, in 24 minutes, the rate constant of decomposition process is
Adiabatic process involves
Which of the following statement is true for ∆G?
An example of anthraquinone dye is
A compound with molecular formula C₇H₁₆ shows optical isomerism , the compound will be
The formula of sodium nitroprusside is
Which of the following compound shows optical isomerism?
The resistance of 1 N solution of acetic acid is 250 ohm, when measured in a cell of cell cosntant 1.15 cm⁻1. The equivalent conductance (in ohm⁻1 cm2 equiv⁻1) of 1 N acetic acid is
If the standard electrode potential of Cu2+/Cu electrode is 0.34 V, what is the electrode potential at 0.01 M concentration of Cu2+? (T = 298K)
A gas X at 1 atm is bubbled through a solution containing a mixture of 1 M– and 1 MZ– at 25°C. If the reduction potential of Z > Y > X, then
Acid rain is due to increase in the concentration of which the following in the atmosphere?
Potassium is extracted by the electrolysis of
The salt which is least likely to be found in mineral is
Density of methane at 250°C and 6 atm. pressure is (R = 0.0821 atm)
A real gas most closely approaches the behaviour of an ideal gas at
The components present in producer gas are
When I₂ is passed through KCl, KF, KBr solutions
The concept that acid is proton donor and base is proton acceptor was given by
Out of the following E1 reaction is favoured in the following case:
When 100 ml of 0.1 M NaOH are added to 50 ml of 0.2 M HCl, at 25°C, the pH of the resulting solution is
Acetamide and ethylamine can be distinguished by reacting with
Natural rubber is a polymer of
In the following, electrophile is:
HO ― NO2
Concentrated nitric acid is added to Lassaigne's extract in the detection of halogen to
Lowering in vapour pressure is the highest for
Which of the following compounds to does not show Lassaigne's test for nitrogen?
Oxidation state of oxygen in hydrogen peroxide is
How many gm. of dibasic acid (Mol.wt. = 200) should be present in 100ml. of its aqueous solution to give decinormal strength?
An ideal solution was obtained by mixing methanol and ethanol. If the partial vapour of methanol and ethanol are 2.619 kpa and 4.556 kpa respectively, the composition of the vapour (in terms of mole fraction) will be
If gold numbers of A, B, C and D are 0.005, 0.5, and 5 respectively, then which of the following will have the greatest protective value?
protective power ∝ 1 / Gold number
Gold number of A is least, therefore, it has the highest protective power.
The equivalent weight of KMnO₄ (formula weight = M) when it is used as an oxidant in neutral medium is
Titanium shows magnetic moment of 1.73 B.M. in its compound. What is the oxidation number of titanium in the compound ?
The thallus of Volvox is called
Three radial vascular bundles are present in
Protonema is found in the life cycle of
A frog has
When a microscope mother cell with 40 chromosomes, undergoes meiosis, then each of the resulting cell will have
Assembly of 60 S and 40 S subunits of ribosome produces
The amphibians of plant kingdom are
A cell divides every minute. It will fill a 100 ml beaker in one Hour. How much time would it take to fill 50 ml beaker
Who proposed the concept of unit membrane for tripartite structure of lipoproteins?
A source of maximum energy is
During protein catabolism, _____ is produced as an end product by the liver.
Complications of aplastic anemia generally do not include:
Linkage map of X-chromosome of fruitfly has 66 map units with yellow body gene (y) at one end and bobbed hair (b) at the other. The recombination frequency between y and b gene would be
A strong mutagen is
Which of the following does not belong with the others?
Compared to blood our lymph has
Human beings have long intestine in order to provide more space for
Test tube baby means a baby born when :
Which of the following acts to inhibit acid production?
Human population growth is :
All of the following are barrier contraceptive devices except the :
The term ecosytem was first coined by
An ecosystem has two components such as
Cranial capacity was highest in
Vitamin B₂ is component of which coenzyme.
Which is not true of enzymes ?
Melanocyte stimulating hormone(MSH) is secreted by pituitary
Adrenal gland is associated with
Conifers occur at the height of
The muscles responsible to move the eye ball are the
If two genes are present at the same locus and after interacting with each other produce different effects are called
An aggregate fruit is an example of
If two alleles come together, only one is able to express itself. This is called :
Mendelian recombinations are due to :
Mammary glands are modified
Organ transplant rejection is prevented by
A person has developed interferon in his body. He seems to carry infection of
Cornea transplantation has become common due to
Mesozoic era was dominated by
O blood group is universal donor because the blood has
Which of the following is an ammonifying bacteria ?
Which one of the following essential elements can land plants normally obtain directly from the air?
Which one is wrong combination
The bacteria (Clostridium botulinum) that cause botulism are
The content of linoleic acid is highest in
Which one of the following is not related to corm?
The brain of cockroach is formed by
Testes of Earthworm occur segments
Which of the following is macronutrient?
The nervous system of cockroach comprises
Oxygen is transported in Earthworm by pigment
Annual rings are distinct in plants growing in
Water storage tissue has
Safranine stains which elements of the tissue
Which of the following would be contained within the central nervous system?
Petiole is modified into a tendril in
Biotic factors refer to
Sugarcane is generally propagated vegetatively because
Which of the following is a true fish ?
Vitamin-E is also called
The Indian soils are generally poor in
Pasteurization is heating at
Which of the following is a pair of biofertilizers?
Parenchyma with large air spaces is
Plant raised from single germinating pollen grain under cultural conditions would be
Yoghurt is formed by
Six-hooked embryo of Taenia is known
Rennin used in cheese industry is an
Which one of the following comprises only simple tissues
Ecological succession on sand is
Fever is caused by
When symptoms do occur, they usually begin four to seven days after you are bitten by an infected mosquito. Dengue fever causes a high fever — 104 F degrees — and at least two of the following symptoms: Headache. Muscle, bone and joint pain.
Entry of sewage in water caused a spurt in the growth of algae but killed fish due to
A cell coded protein, formed in response to viral infection, is
Large gap between birth and death rates will result in
Acid rain is due to the pollution of
Intergeneric crosses are rarely successful under natural conditions. Which of the following methods may be beneficial in this regard
Movement of pollen tube towards embryo sac is
The duct that is used by both the reproductive and excretory systems in males is the
Which one diploid
The genetic sex of a child is determined by the
Testosterone in the adult male is produced by the
Most of our food crops and fodder crops belong to family-
Which of the following structures requires a hypertonic environment to function?
Increasing the levels of aldosterone in the blood would result in
increasing aldosterone means that more sodium ultimately winds up in the blood, activating thirst mechanisms which increases ECF(extracellular fluid) volume and therefore increases blood pressure. (if you raise blood volume, you raise blood pressure)
The sperm penetrates the egg by means of enzymes that are found in the
Which of the following family plants having tricarpellary, syncarpous unicellular gynoecium with inferior ovary -
The excretory system regulates the amount of bicarbonate ion (HCO3) in the blood in order to maintain homeostatic levels of