In LR-circuit, the value of impedance is 50Ω and the resistance is 25 Ω. The value of power factor of the circuit is
Fraunhofer spectrum is a
The image of the sun is formed on the photosensitive metal with a convex lens and the photoelectric current is I . If the lens is replaced by another similar lens of half the diameter and double the focal length, then photoelectric current will be
An X - ray tube is operated at a constant potential difference and it is required to get X - ray of wavelength not less then 0.2 nano-metres. Then the potential difference in kilo-volts is [h = 6.63 x 10−34 J-sec ; e = 1.6 x 10−19 C ; c = 3 x 108 ms−1]
The potential difference between the terminals of a cell in open circuit is 2.2 volts. With resistance of 5 ohm across the terminals of a cell, the terminal potential difference is 1.8 volt. The internal resistance of the cell is
Two wires of the same material are given. The first wire is twice as long as the second and has twice the diameter of the second. The resistance of the first will be
A particle of mass m moves with constant speed along a circular path of radius r under the action of force F. Its speed is
In photo electric effect the stopping potential is
In the photoelectric effect is that the stopping potential is a function of the frequency of the incident light. As shown in Figure, there is even a cutoff frequency ν0 below which there is no photoelectric effect occurs, regardless of the intensity of the light.
A plot of stopping potential vs. frequency of incident light (Cathode: Sodium ; Cutoff frequency νo =4.39x 1014 Hz
Hence option (A) is correct.
An electron of charge 'e' coulomb passes through a potential difference of V volts. Its energy in 'joules' will be
The energy of a photon of light with wavelength 5000Å is approximately 2.5eV. This way the energy of an X-ray photon with wavelength 1Å would be
During X-ray formation if voltage is increased
A bar magnet is released into a copper ring which is directly below it. What about the acceleration of the magnet?
The pressure exerted by an electromegnetic wave of intensity I on a non-reflecting surface is (where c = Velocity of light)
Heat radiations propagate with the speed of
The capacity of a condenser with two identical plates separated by a distance 'd' in air is 'C'. If the distance of separation is reduced to d/2 , the capacity is
If the distance between the plates of a parallel plate condenser is halved and the dielectric is doubled, then its capacity increases by
Which of the following is the example of ideal black body
The value of g on the moon is 1/6th that on earth. A body weighing 60 kg on the earth, has weight on the moon
The factor not needed to calculate heat lost or gained when there is no change of state, is
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
A circular disc of radius 0.2 meter is placed in a uniform magnetic field of induction in such a way that its axis makes an angle of . The magnetic flux linked with the disc is
Relative permittivity and permeability of a material are ℇr and μr , respectively . Which of the following values of these quantities are allowed for a diamagnetic material ?
Nickel shows ferromagnetic property at room temperature. If the temperature is increased beyond Curie temperature, then it will show
The extension in a string, obeying the Hooke's law, is x. The speed of sound in the stretched string is v. If the string is extended to 1.5 x, then speed of sound will be
Speed of sound in a stretched string
Where T is the tension in the string and μ is mass per unit length
According to Hooke's law, F ∝ x
The radio - isotope of this element is used in the treatment of cancer
A capillary tube (A) is dipped in water . Another identical tube (B) is dipped in a soap water solution . Which of the following shows the relative nature of the liquid columns in two tubes ?
In a nuclear reactor the excess reactivity can be controlled by using ---- rods
When two deuterium nuclei fuse together, in addition to tritium, we get a
Time period of a simple pendulum of length l is T1 and time period of a uniform rod of the same length l pivoted about one end and oscillating in a vertical plane is T2. Amplitude of oscillations in both the cases is small. Then T1/T2 is
With respect to air, critical angle in a medium for light of red colour [λ₁] is θ. Other facts remaining same, critical angle for light of yellow colour [λ₂] will be
In an experiment to determine the focal length (f) of a concave mirror by the u–v method, a student places the object pin A on the principal axis at a distance x from the pole P. The student looks at the pin and its inverted image from a distance keeping his/her eye in line with PA. When the student shifts his/her eye towards left, the image appears to the right of the object pin. Then,
The moment of inertia of a cylinder of radius R, length l and mass M about an axis passing through its centre of mass and normal to its length, is
A spherical ball rolls on a table without slipping. Then the fraction of its total energy associated with rotation is
A particle starts S.H.M. from the mean position. Its amplitude is A and time period is T. At the time when its speed is half of the maximum speed, its displacement y is
A semiconductor is cooled from T₁K to T₂K. Its resistance
The difference in the variation of resistance with temperature in a metal and a semiconductor arises essentially due to the difference in the
Two wires have resistance of 2Ω and 4Ω connected to same voltage, ratio of heat dissipated at resistance is
If m is the mass, θ is temp. and 's' is specific heat, then thermal capacity k is given by
The work done in an adiabatic change in a gas depends only on
The dimensional formula for impulse is
A string in musical instrument is 50 cm long and its fundamental frequency is 800 Hz. If a frequency of 1000 Hz is to be produced, then required length of string is
A source and a listener are moving towards each other with a speed 1/10th of the speed of sound. if the frequency of the note emitted by the source is f, the frequency of the note heard by the listner will be nearly
Two bodies with kinetic energies in ratio of 4 : 1 are moving with equal linear momentum. The ratio of their masses is
An engine pumps water continuously through a hose. Water leaves the hose with a velocity v and m is the mass per unit length of the water jet. What is the rate at which kinetic energy is imparted to water?
The change of momentum in each ball of mass 60 gm, moving in opposite directions with speeds 4 m/s collides and rebounds with the same speed is
Which of the following cannot be made by using Williamson's synthesis?
Which of the following reactions is used for detecting presence of carbonyl group ?
Which of the following set of quantum numbers is correct for an electron in 4f-orbital?
Sodium chloride imparts a yellow colour to the Bunsen flame. This can be interpreted due to the
Sodium ions after absorbing heat energy from the bunsen flame emit excess energy in the form of yellow light in the visible region
Which of the following compound acts both nucleophile as well as an electrophile?
Isoelectric point is the pH at which
Oxidation of toluene to benzaldehyde by the use of chromyl chloride is called
In CCl₄, the four valencies of carbon are directed towards the corners of a
The no. and types of bonds between two carbon atoms in calcium carbide are
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 law formulated by Nernst is
The rate, at which a substance reacts at constant temperature, depends upon its
If reaction between A and B to give C shows first order kinetics in A and second order in B, the rate equation can be written as
Plants and living beings are the examples of
Which one of the following is an example of exothermic reaction?
Acetoxybenzoic acid is
Which of the following molecules will be optically active ?
The co-ordination number and oxidation number of X in [XSO₄(NH₃)₅]Cl is
In any ferric salt, on adding potassium ferrocyanide, a prussian blue colour is obtained, which is mainly due to the formation of
In the cell, Zn | Zn2⁺ ∥ Cu2⁺ | Cu, the negative terminal is
In the reaction: Ag₂O + H₂O₂ → 2Ag + H₂O + O₂, the H₂O₂ acts as
Aluminium displaces hydrogen from acids,but copper does not. A galvanic cell prepared by combining Cu/Cu2⁺ and Al/Al3⁺ has an EMF of 2.0 V at 298 K. If the potential of copper electrode is + 0.34 V,that of aluminium electrode is
Positive pollution of soil is due to
Formula of Plaster of Paris is
The chemical formula of gypsum is
A gas is initially at 1 atm pressure. To compress it to 1/4 th of its initial volume, pressure to be applied is
50 ml of hydrogen gas diffuses out through a small hole from a vessel in 20 minutes, time needed for 40 ml of oxygen to diffuse out is
Which of the following statement is correct with respect to the property of elements with increase in atomic number in the carbon family(group 14)?
Which of the following halogens exhibit only one oxidation state in its compounds?
A white salt is readily soluble in water and gives a colourless solutions with a pH of about 9.The salt would be
The pH of blood is
Arrange the following :
(CH₃)₃N(IV) in increasing order of basicity in aqueous medium
Identify the compound out of the following in which complete delocalisation of π − electrons does not take place?
Which gives more stable product ?
The raw material used in making nylon-66 is
If nitrogen and sulphur both are present in an organic compound, then during the Lassaigne's test, both will change into
Steam distillation is used for the purification of
The oxidation number of Ni in Ni(CO)₄ is
A 1% aqueous solution (mass by volume) of a certain substance is isotonic with a 3% solution of dextrose, i.e. glucose (molar mass 180) at a given temperature. The molar mass of the substance is
A 500 g tooth paste sample has 0.2 g fluoride concentration. What is the concentration of F in terms of PPm level ?
Isotonic solutions at a particular temperature have the same
The concentration of electrolyte required to coagulate a given amount of As₂S₃ solution is minimum in case of
How many 'd' electrons are present in Cr2⁺ ion ?
Transition metals are often paramagnetic owing to
Fern prothallus is
When moss spores germinate they form
Well developed pith is found in
Brachymeiois consists of
Stages in proper sequence of prophase I are
Structure present in man but absent in frog is
The diameter of mitochondria is
Correct sequence of protein(P) an lipid (L) in cell membrance is
Living cells can be studied by
Which of the following might trigger erythropoiesis?
Daughter of a colourblind father and normal mother marries a colourblind person. The family will have colourblindness in
Presence of recessive trait is 16%. The frequency of dominant allele in population is
Which of these can dissolve a blood clot?
A false positive result is best described as one that is given
A false positive error, or false positive, is a result that indicates a given condition exists when it does not. For example, a pregnancy test which indicates a woman is pregnant when she is not, or the conviction of an innocent person.
Neutrophils promote adhesion of neutrophils to endothelium, attract other neutrophils, monocytes and eosinophils and dilate capillaries by secreting
Cryptorchidism is a condition in which
The first case of IVF-ET technique success, was reported by :
Causative agent of syphilis is :
During menstruation the level of progesterone in the blood is
Pyramid of numbers in a grassland/true ecosystem is
Which of the following are liver waste products?
Food is directed towards caecum and colon accordingly at the point
Great Barrier Reef along east coast of Australia is a
The organ which was considered vestigial till recently but now confirmed to be endocrine gland is
Which of the following plant produces seeds but not flowers ?
Megasporophylls which are arranged spirally and acropetaly on the central axis of the female cone of Pinus bear -
In Medelian genetics one of the following character is the dominant
Specificity of protein in enzyme action depends upon
Which of the following came after Dryopithecus during the evolution of man?
Energy released from enzyme-substrate interaction is
Monohybrid cross involves individuals :
Source of mendelian recombinations is
Who discovered vaccine against small pox?
Blood group AB has
Antibody formation and immunity production by globulin protein is found in
Sequence of eye covering (outer to inner) is
In fishes the kidney is
Which is wrong
Bacteria differ from viruses in
Which is involved in body defence?
A number of organic compounds can be decomposed by
Which is connecting link?
Unsaturated fats are made saturated by
The number of ovarioles in each ovary of cockroach is
Role of inorganic nutrients in plant growth and metabolism was first discovered by
Brown heart disease is due to deficiency of
Basic unit in the eye of Cockroach is
Hill reaction occurs in
In Pheretima, septa are absent between which segments?
Blood vascular system of earthworm is
Resin canals are
Plants with soft stem are called
At maturity, which of the following is non-nucleated ?
Secondary phloem remains functional generally
Secondary phloem can remain active over several growth cycles. Secondary phloem, like secondary xylem, is a complex tissue. It always has sieve elements which are analogous to tracheary elements. Secondary phloem remains functional generally as long as plant is alive.
Bony plates alongwith scales is characteristic of
Transgenic crops are useful as they have genes of
Which of the following cranial nerves innervates heart, stomach and lungs?
Animals loving darkness are
Submerged hydrophytes exchange gases through
Mycorrhiza acts as
Advancement in genetic engineering has been possible due to discovery of
H.G.Khorana was awarded the Nobel prize for
Glucose fermentation by yeast yields
The chemical knives (scissors) used in genetic engineering is
Which of the following crops have been brought to India from new world?
Conversion of nitrites into nitrates is carried out by
Intermediate host of Liver Fluke is
Vascular bundles in the stem of Cucurbita or Lagenaria or cucurbitaceae are
The most harmful environmental pollutants are
Hard lignified thick-walled long and pointed cells constitute
Green house effect was first described by
Automobile exhaust gas that causes major respiratory problem is
The term succession was coined by
Plants of edible banana are propagated by
A parasite living within tissue of host is
Insulin (bovine) has 51 amino acids in A and B polypeptides. The polypeptide A possesses amino acids
The egg apparatus in a nature embrayo sac consists of
if pollen of a flower falls on the stigma of anther flower, belonging to the same plant, it is called
Cryptorchidism is a condition in which testes are
Cryptorchidism is a congenital disorder when one or both of a newborn's testicles fail to descend into the scrotum. Although this condition may occur on both sides, it more commonly affects the right testis. Because the testicles normally descend into the scrotum during the eighth month of gestation, undescended testicles most commonly affect newborns
The families having common characters constitute an -
When mammary glands of male develop similar to female, the condition is known as
When sperm is ejaculated, it comes into contact with or passes near each of the following structures. Which sequence correctly describes the passage of sperm out of the body?
Pollen grain is related to embryo sac as
High blood pressure can be the result of