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A low-loss transformer has 230 volts applied to the primary and gives 4.6 volts in the secondary. Secondary is connected to a load which draws 5 ampere of current. The current (in ampere) in the primary is
The particles emitted by radioactive decay are deflected by magnetic field. The particles will be
A car is initially at rest on a circular track that has a radius of 40 m. The car then starts to move counter clockwise around the track, accelerating at constant angular acceleration of 1.0 rad/s2. The time it takes for the car to move half of the way around the track is
If the ratio of the concentration of electrons to that of holes in a semiconductor is 7/5 and the ratio of the currents is 7/4, then what is the ratio of their drift velocities?
A body of mass 2Kg moving with a velocity of 6 ms-1 strikes inelastically another body of same mass at rest. The amount of the heat evolved during collision is
According to Hooke's law of elasticity, the ratio of stress to strain
Reactance of a capacitor of capacitance C μ F for a.c. of frequency 400/π Hz is 25 Ω. The value of C is
The plates of a parallel plate capacitor are charged upto 200 volts. A dielectric slab of thickness 4 mm is inserted between its plates. Then to maintain the same potential difference between the plates capacitor, the distance between the plates is increased by 3.2 mm. The dielectric constant of dielectric slab is
A block of 1 kg is stopped aganist a wall by aplying a force F perpendicular to the wall. If μ = 0.2 then minimum value of F will be
F = W/μ = 1 x 9.8/0.2 = 49 N
Choose the correct statement from the following. The radius of the orbit of a geostationary satellite depends upon
Consider two rods of same length and different specific heatrs (s₁ and s₂) conductivities k₁ and k₂ and areas of cross section (A₁ and A₂) and both giving temperature T₁ and T₂ at their ends. If the rate of heat loss due to conduction is equal, then
At 27oC temperature, the kinetic energy of an ideal gas is E1. If the temperature is icnreased to 327oC, then kinetic energy would be
Average kinetic energy of gas molecules
E = 3/2 RT/N
R = ideal constant
N = Avogadro number
∴ E ∝ T
Hence, E1/E2 = T1/T2
E1/E2 = 27 + 273/327 + 273
E1/E2 = 300/600
∴ E2 = 2E1
Consider the following statements concerning electrons :(I) Electrons are universal constitutents of matter (II) J.J. Thomson received the very first Nobel Prize in Physics for discovering the electron (III) The mass of the electron is about 1/2000 of that of a neutron (IV) According to Bohr the linear momentum of the electron is quantised in the hydrogen atom. Which of the above statements are NOT correct ?
A body of mass 60 kg is dragged with just enough force to start moving on a rough surface with coefficients of static and kinetic frictions 0.5 and 0.4 respectively. On applying the same force, what is the acceleration :
F - f = ma
⇒ fs - fk = ma
or, μsmg - μkmg = ma
⇒ g(μs - μk) = a
⇒ 9.8 (0.5 - 0.4) = a
∴ α = 0.98 ms-2
Magnetic field to a current carrying conductor is propotional to
Oil spreads over the surface of water, whereas water does not spread over the surface of oil, because
A passenger train is moving at 5 m−s-1. An express train is travelling at 30 m−s-1, on the same track and rear side of the passenger train at some distance. The driver in express train applied brakes to avoid collision. If the retardation due to brakes is 4 m−s-1, the time in which the accident is avoided after the application of brakes is
A 100 kg car is moving with a maximum velocity of 9 m/s across a circular track of radius 30 m. The maximum force of friction between the road and the car is
A car of mass 400 kg travelling at 72 kmph crashes into a truck of mass 4000kg and travelling at 9 kmph in same direction. The car bounces back at a speed of 18 kmph. The speed of the truck after the impact is
A coin is placed on a horizontal platform, which undergoes vertical simple harmonic motion of angular frequency ω. The amplitude of oscillations is gradually increased. The coin will have contact with the platform for the first time. (i) at the higher position of the platform (ii) at the mean position of the patform (iii) for an amplitude of g/ω2 (iv) for an amplitude of √2/ω
A stone thrown at an angle θ to the horizontal reaches a maximum height h. The time of flight of the stone is
A ray of light strikes a material's slab at an angle of incidence 600 . If total reflected and refracted rays are perpendicular to each other, the refractive index of the materials is
The moment of inertia of a sphere of radius R and mass M about a tangent to the sphere is
Consider the following statements about dimensions
P:Force=acceleration due to gravity x mass
Q:Electric charge=current x time
R:Magnetic flux=Electric voltage x time
The correct statements are :
Force necessary to pull a circular plate of 5 cm radius from water surface for which surface tension is 75 dynes/cm,is
The total length of the circular plate on which the force will act = 2πR
Force to pull = 2πRT = 2 x π x 5 x 75 = 750π dynes
The negative Zn pole a Daniell cell, sending a constant current through a circuit, decreases in mass by 0.13g in 30 minutes. If the electrochemical equivalent of Zn and Cu are 32.5 and 31.5 respectively, the increase in the mass of the positive Cu pole in this time is
The pressure of a given mass of gas is 100 cm at 127oC . The pressure of the same mass of gas having the same volume at 27oC is ......
The dimension of capacitance is (where Q is the dimension of charge)
Two waves are given by y₁ = a sin (ωt - kx) and y₂ = a cos (ωt - kx). The phase difference between the two waves is
A particle of mass m moving with velocity ν collides with a stationary particle of mass 2 m and sticks to it. The speed of the system, after collision, will be
Which of the following organic compounds exhibits positive Fehling test as well as Iodoform test?
The total number of electrons in a nitrate ion will be (At. nos: N = 7 and O = 8)
2,3-dimethyl hexane contains .... tertiary, .... secondary and ..... primary carbon atoms respectively.
On addition of aqueous NaOH to a salt solution, a white gelatinous precipitate is formed, which dissolves in excess alkali. The salt solution contains
How many atoms are contained in one mole of sucrose (C12H22O11)?
C12H22O11 contains a total of 45 atoms ≅ 45 x 6.02 x 1023 atoms/mole
Which of the following compounds will not react with ethanolic KCN?
The molar heat capacity of water at constant pressure C is 75 JK1 mol-1.When one KJ of heat is supplied to 100 g of water which is free to expand ,the increase in temperature of water is
According to Le-Chatelier's principle, adding heat to a solid and liquid in equilibrium will cause the
For a reaction : 2A + B → Products, the active mass of B is kept constant and that of A is doubled. The rate of reaction will then
The amount of heat required to raise the temperature of a body temperature through 1oC is called, its
The number of possible structural isomers of C₄H₁₀O is
The oxide of which of the following elements will be acidic in character
The oxides of metals are basic whereas the oxides of non-metals are acidic.
50 ml of gas A diffuses through a membrane in the same time as for the diffusion of 40 ml of a gas B under identical pressure-temperature conditions. If molecular weight of A is 64 that of B would be
Which of the following compound possesses the C ― H bond with the lowest bond dissociation energy?
The molecular formula of a saturated compound is C2H4Cl2. The formula permits the existence of two :
Which of the following compounds gives blood red coloration when its Lassaigne's extract is treated with alkali and ferric chloride?
In which case product formed is identical in the absence or presence of peroxide?
A is a lighter phenol and B is an aromatic carboxylic acid.Separation of a mixture of A and B can be carried out easily by using a solution of
Which of the following reactions involves oxidation and reduction?
The major binding force of diamond, silicon and quartz is
On dissolving 1 mole of each of the following acids in 1 litre water, the acid does not give a solution of strength 1 N is
A compound contain 69.5% oxygen and 30.5% nitrogen and its molecular weight is 92. The formula of the compound is
The tests that are used in the diagnosis of AIDS are :
Which of the following animal is the most economical 'Meat making machine'?
When the cleavage in the egg passes across the centre on animal and vegetal axis, it is known as :
Microlecithal eggs with small amount of food reserve are found in :
Waston and crick are known for their discovery that DNA is
An example of unstriated muscles which are entirely involuntary are located
Which molecule provides ATP during muscle contraction?
A nerve to the heart is severed, resulting in a decreased heart rate. The severed nerve was likely
The heart is innervated by vagal and sympathetic fibers. The right vagus nerve primarily innervates the SA node, whereas the left vagus innervates the AV node; however, there can be significant overlap in the anatomical distribution.
The specific function of light energy in the process of photosynthesis is to
In Photosystem I, light energy activates electrons of the Photosystem II pigments. These pigments transfer the energy of their excited electrons to a special Photosystem II chlorophyll molecule, P680, that absorbs light best in the red region at 680 nanometers.
Increase in the concentration of pollutants in higher trophic levels is called
Natural parthenogenesis is found in
Parthenogenesis is a form of asexual reproduction found in females, where growth and development of embryos occurs without fertilization by a male. Naturally occurring parthenogenesis can take place in a variety of species under a number of different circumstances. Honey Bees tend to use parthenogenesis for the establishment of social organization. The male drones, or worker bees, reproduce solely through parthenogenesis. All females, both fertile queens and infertile workers, are created through sexual reproduction.
In pelvic girdle the articulation of the iliac surfaces with sacrum helps in
A crop plant that can grow well is nitrogen deficient soils without addition of manure is -