The capacity of a pure capacitor is 1 farad. In dc circuits, its effective resistance will be
(1) Zero
(2) Infinite
(3) 1 ohm
(4) 1/2 ohm
Out of the following four statements, how many of them are correct for Fucus?
I. Life – cycle is diplontic.
II. Fertilisation is internal.
III. Sexual reproduction is oogamous.
IV. Frond is photosynthetic.
1. 4
2. 3
3. 2
4. 1
Which of the following is not an example of algae in which there is post – fertilization development process?
1. Laminaria
2. Porphyra
3. Polysiphonia
4. Batrachospermum
Fresh water form is rare in which algal group
1. Red Algae
2. Brown algae
3. Green Algae
4. Both 1. and 2.
Which of the following is not matched correctly?
1. | Artificial system of classification – Equal weightage to vegetative and sexual character. |
2. | Natural system of classification – Based on natural affinities. |
3. | Phylogenetic system – Common ancestor for unrelated taxa. |
4. | Numerical taxonomy – Equal importance to all character. |
Which of the following character is common for all algal group.
1. Presence of cellulose in cell – wall.
2. Starch is reserve food material.
3. Presence of motile stage.
4. Only oogamous type of sexual reproduction.
Study the diagram given below, and find out how many of the statements given below is related to this diagram.
I. It is source of food.
II. Its wall has poly sulphated esters.
III. Its reserve food is similar to glycogen in structure.
IV. There is no motile stage in its life – cycle.
1. 1
2. 2
3. 3
4. 4
Pyrenoids in green algae is located in?
1. Cytoplasm
2. Chloroplast
3. Vacuole
4. Flagella
Following diagram represents a class of algae.
Find out odd statements related to this class of algae.
1. In protoplast a centrally located vacuole is present.
2. Body color depends upon concentration of fucoxanthin.
3. Pyriform zoospore with laterally inserted unequal flagella.
4. Food is stored in form of simple carbohydrates.
Along with Lichens which group of plant play important role when succession takes place on rock.
1. Algae
2. Bryophytes
3. Pteridophytes
4. Angiosperm
Study the diagram given below and mark the correct statement.
1. Part A is dependent on part B.
2. Part B is dependent on part A.
3. Both parts are independent
4. Part A is haploid whereas part B is diploid
Gemma is
1. Green unicellular, asexual bud
2. Green, multicellular, asexual bud
3. Both 1 and 2
4. Green, Filamentous, asexual bud.
Find out incorrect match.
Character |
Liverworts |
Mosses |
|
1 |
Rhizoids |
Unicellular |
Multicellular |
2 |
Zygote |
Immediate meiosis |
Meiosis delayed |
3 |
Fertilisation |
with the help of water |
with the help of water |
4 |
Dominant Stage |
Haploid |
Haploid |
Budding in mosses is mode of vegetative reproduction it takes place in?
1. Primary protonema
2. Secondary protonema
3. Both 1. and 2.
4. Leafy stage.
Although pteridophytes are first land vascular plant but its distribution is restricted to few geographical areas because?
1. Restricted requirement for growth of gametophyte.
2. Need of H2O for fertilization
3. Dominant sporophytic phase
4. Both 1 and 2
Study the diagram given below and find out incorrect statement related to this
1. It has macrophytes
2. It is heterosporous
3. Its gametophyte is independent
4. It lacks vascular tissue
Which of the following feature in pteridophyte considered as an important step in evolution.
1. Presence of cone
2. Presence of two type of leaf
3. Heterospory
4. Seed habit
Which of the following statement is wrong for gymnosperm?
1. They are homosporous.
2. The multicellular female gametophyte is retained within megasporangium.
3. Pollen grain is released from the microsporangium and carried by wind, which come in contact with ovules.
4. The male and female gametophytes do not have an independent free living existence.
Which of the following statement is true for Pinus?
1. Roots have fungal association in the form of mycorrhiza
2. Male and female strobili borne on same tree
3. Both 1 and 2
4. Roots are called coralloid roots
Mark the wrong statement about Cycas
1. Stem unbranched
2. Pinnate leaves persist for few years
3. Roots associated with cyanobacteria
4. Male and female reproductive structure on same plant
Which among the following pteridophytes has compact structure strobili formed by sporophylls as well as it shows heterospory?
1. [A]
2. [B]
3. [C]
4. All the above
Which among the following is/are the life cycle pattern of colonial algae Volvox?
1. A
2. B
3. C
4. All of these
Which one is correct about male and female gametophyte?
1. In bryophytes and pteridophytes they have independent free-living existence
2. In gymnosperms and angiosperms they have no independent free-living existence
3. Both 1 and 2
4. In bryophytes, pteridophytes and angiosperms they have free-living life. They remain in sporangia which retained on sporophytes
For gymnosperms pollination, which is correct?
1. By water
2. It is direct
3. On-ovary
4. It is indirect
Which of the following statement is not true about the family Liliaceae?
1. | Perennial herbs with underground bulbs/corms/rhizomes |
2. | Flower: bisexual, zygomorphic |
3. | Gynoecium: tricarpellary, syncarpous, superior, trilocular with many ovules, axile placentation |
4. | Tulip, Gloriosa, Aloe, Asparagus and colchicum belongs to Liliaceae |
Find odd one out with respect to presence of endosperm in seed
1. Castor
2. Wheat
3. Maize
4. Orchids
Which of the following are true for cyanobacteria?
(I) | They are freshwater/marine or terrestrial algae. |
(II) | Often form blooms in unpolluted water bodies |
(III) | Maybe unicellular, colonial, or filamentous. |
(IV) | Some of them fix atmospheric nitrogen. |
1. I, III, IV
2. I, II, III, IV
3. II, III, IV
4. I, II, IV
Which of the following is true for the reproduction of bacteria?
1. Reproduce mainly by fission.
2. Under unfavourable conditions, they produce spores.
3. Also reproduce by sort of sexual reproduction.
4. All of these
Which of the following are correct for viroids?
(I) Discovered by Pasteur.
(II) Smaller than viruses.
(III) Found to be free DNA.
(IV) Cause potato spindle tuber disease.
(V) Nucleic acid has high molecular weight.
1. I, III, IV
2. II, III, IV, V
3. II, IV
4. II, IV, V
What is absent in Euglenoids?
1. Two flagella, a short and a long one.
2. Pellicle, a protein-rich layer.
3. Pigments identical to those present in higher plants.
4. Cell wall with stiff cellulose plates.
Which of the following form the basis for the division of the kingdom fungi into various classes?
(I) | Mode of spore formation and fruiting bodies. |
(II) | Morphology of the mycelium. |
(III) | Mode of nutrition and occurrence. |
1. | I, II | 2. | I, III |
3. | II, III | 4. | Only I |
Identify A, B, and C in the given diagram:
A |
B |
C |
|
1 |
Sheath |
Head |
Collar |
2 |
Collar |
Head |
Sheath |
3 |
Sheath |
Collar |
Head |
4 |
Head |
Collar |
Sheath |
Paramecium and Amoeba are placed in kingdom protista with
1. Anabaena and Colletotrichum
2. Anabaena and Chlorella
3. Chlamydomonas and Colletotrichum
4. Chlorella and Chlamydomonas
Which of the following is not the characteristic of the class to which Mucor belongs?
1. Mycelium is aseptate and coenocytic
2. Zygospore is formed by fusion of two gametes
3. Asexual reproduction takes place by zoospores or aplanospores
4. Gametes are always dissimilar in morphology
Earlier classification systems included bacteria, blue green algae, fungi, mosses, ferns, gymnosperms and angiosperms under plants. The character that unified this whole kingdom was that all the organisms included had
1. Cell wall in their cells
2. Nuclear membrane in their nucleus
3. Autotrophic nutrition
4. All of these
Which of the following statements is true for Heterotrophic bacteria?
1. | They fix nitrogen in legume roots. |
2. | The majority are important decomposers. |
3. | Helpful in making curd from milk and production of antibiotics. |
4. | All of these. |
Who showed that viruses could be crystallized and crystals consist largely of proteins?
1. D.J. Ivanowsky
2. M.W. Beijerinek
3. W.M. Stanley
4. T.O. Diener
Which of the following is not true for chrysophytes?
1. Found in fresh water as well as in marine environment.
2. Cell membranes are embedded with silica.
3. Most of them are photosynthetic.
4. Microscopic and float passively in water currents.
How many plants in the list given below have marginal placentation?
Mustard, Gram, Tulip, Asparagus, Arhar, Sunn hemp, Chilli, Colchicum, Onion, Moong, Pea, Tobacco, Lupin
1. Four
2. Five
3. Six
4. Three
Match the following list of bioactive substances and their roles:
Bioactive Substances: -
(i) Statins (ii) Cyclosporin A (iii) Streptokinase (iv) Lipase
Role-
A. Removal of oil stains
B. Removal of clots from blood vessels
C. Lowering of blood cholesterol
D. Immuno-suppressive agent
Choose the correct match:
1. i B, ii C, iii A, iv D
2. i D, ii B, iii A, iv C
3. i B, ii A, iii D, iv C
4. i C, ii D, iii B, iv A
Match the items in Column ‘A’ and Column ‘B’ and choose correct answer:
Column A |
Column B |
(i) Lady bird |
(A) Methanobacterium |
(ii) Mycorrhiza |
(B) Trichoderma |
(iii) Biological control |
(C) Aphids |
(iv) Biogas |
(D) Glomus |
The correct answer is:
1. i B, ii D, iii C, iv A
2. i C, ii D, iii B, iv A
3. i D, ii A, iii B, iv C
4. i C, ii D, iii A, iv A
Mycorrhiza does not help the host plant in:
1. Enhancing its phosphorus uptake capacity
2. Increasing its tolerance to drought
3. Enhancing its resistance to root pathogens
4. Increasing its resistance to insects
Biological Pest Control methods are more preferably used because-
1. Chemical pesticides are discriminate
2. Predators work through check and balance
3. Predators are indiscriminate
4. All of above
Which of the following statement is incorrect?
1. Trichoderma is free living fungi, present in root ecosystem acts as biocontrol agent
2. Genus of baculoviruses is species group specific broad spectrum insecticide
3. All harmful insect pests should be kept at manageable level as it furthers biodiversity
4. Ladybird and Dragonflies are used as biocontrol agent
Read the following four statements (I – IV), find out certain mistakes in two of them.
I: In our stomach lactic acid bacteria play beneficial role by checking growth of disease causing microbes.
II: Lactic acid bacteria produce acid that coagulates and completely digests the milk protein.
III: Lactic acid bacteria improve the nutritional quality by increasing the amount of Riboflavin
IV: Lactic acid bacteria require suitable temperature for their multiplication.
Which of the above two statements are not correct?
1. Statements I and II
2. Statement I and III
3. Statement II and III
4. Statements II and IV
In high yielding hybrid crop varieties to exploit hybrid vigour, the farmers need to purchase fresh hybrid seed every year because
1. They are not allowed to grow their own seed
2. Hybrid vigour is lost due to inbreeding depression
3. It is cheaper to purchase fresh seed
4. None
Citric acid is produced by
1.Clostridium
2.Aspergillus niger
3.Acetobacter
4.Lactobacillus
Yeast is used in the production of
1. Bread and Beer
2. Cheese and Butter
3. Citric acid and Lactic acid
4. Lipase and Pectinase
Pusa komal is disease resistance variety of?
1. Cauliflower
2. Brassica
3. Cowpea
4. Chilli
Virus free plants can be obtained by
1. Only apical meristem
2. Only axillary meristem
3. Apical and axillary meristem
4. Embryo culture
Which of the following in not the objective of bio fortification
1. Improvement of protein content and quality.
2. Increase oil content & quality
3. Reduction in micro nutrient and mineral content.
4. Improvement of vitamin content
Atlas 66 is a variety of
1. Wheat
2. Bhindi
3. Rice
4. Sugar cane
The most practical means to improve public health and enriching foods with vitamins and minerals would include.
1. Micropropagation
2. Use of single cell proteins
3. Biofortification
4. Developing pest resistant crops
By cross hybridisation of Saccharum barberi and Saccharum officinarum sugarcane varieties obtained have the desired qualities except one of the following
1. High yield.
2. High levels of sugar.
3. Resistance to jassids.
4. Thick stems.
Which of the following varieties is not associated with the increase in rice production during green revolution.
1. IR8
2. Jaya
3. Kalyan Sona
4. Ratna
Find the wrong match.
1. Wheat → Pusa Shubra
2. Cauliflower → Pusa Snowball K-1
3. Chilli → Pusa Sadabahar
4. Brassica → Pusa Swarnim
Somaclones are produced by
1.Micropropagation
2.Mutation
3.Polyploidy
4.Hybridisation
In wheat, stem sawfly unable to cause destruction of crop due to
1.Low nitrogen and sugar content
2.Hollow stem
3.Solid stem
4.Nectar-less flowers
Classical plant breeding involves:
1. Hybridisation of pure lines
2. Domestication
3. Tissue culture
4. Using molecular genetic tools
Resistance to yellow mosaic virus in Abelmoschus esculentus was transferred from a wild species and a new variety was produced, which is called:
1. Pusa sawani
2. Pusa A-4
3. Parbhani kranti
4. Himgiri
High aspartic acid, low nitrogen and sugar content in maize lead to resistance in maize against:
1. Aphids
2. Stem borers
3. Jassids
4. Stem sawfly
Select the incorrect statement with respect to Atlas 66:
1. A wheat variety having high protein content
2. Used as a donor for improving cultivated wheat
3. Is a variety of mexican dwarf wheat
4. Has been used for biofortification
Find the mis-match:
1. Explant - Plant part used for tissue culture
2. Somaclones - Variations produced during micropropagation
3. Callus - Undifferentiated mass of cells
4. Totipotency- Capacity to generate a whole plant from any cell
Select the mis-match:
1. Monascus purpureus - Statins
2. Trichoderma polysporum - Cyclosporin-A
3. Clostridium butylicum - Citric acid
4. Streptococci - Streptokinase
Nucleopolyhedrovirus are:
1. Broad-spectrum insecticides
2. Effective against several plant pathogens
3. Harmful to non-target insects
4. Used as biological control agents
The distillation of the fermented broth is required in the formation of
A. rum
B. beer
C. brandy
D. whisky
1. A, B, C
2. A, C, D
3. B, C, D
4. A, B, D
The technology of biogas production in India has been developed by the efforts of
A. Khadi and Village Industries Commission (KVIC)
B. Indian Council of Agricultural Research (IARI)
C. Indian Agricultural Research Institute (IARI)
D. Indian Council of Medical Research (ICMR
1. A, C, D
2. C, D
3. A, C
4. A, B
The best breeding method for animals that are below average in productivity in milk production is:
1. Inbreeding
2. Out crossing
3. Cross breeding
4. Interspecific hybridization
To induce follicular maturation and super-ovulation, a cow is administered a hormone with activity like:
1. FSH
2. LH
3. Estrogen
4. Progesterone
Which of the following is a freshwater edible fish?
1. Hilsa
2. Mackerel
3. Pomfret
4. Common carp
The reduced biological fitness in a given population as a result of breeding of related individuals is called as:
1.Heterosis
2.Heterozygote advantage
3 Inbreeding depression
4.Saltation
In MOET, the fertilized eggs at 8 – 32 cells stage is transferred to the surrogate rather than the genetic mother because:
1 The surrogate chosen is of a different breed from the genetic mother
2.The surrogate mother is of a younger age
3.The genetic mother is available for another round of super ovulation
4.The genetic mother is of an inferior breed
Arrange the main steps of plant breeding sequentially
I. Cross-hybridisation among the selected parents.
II. Evaluation and selection of parents.
III. Selection and testing of superior recombinants.
IV. Testing, release and commercialization of new cultivars.
V. Collection of variability.
1. II V I IV III
2. V II III I IV
3. V II I III IV
4. II I V III IV
Germplasm collection is in the form of
1. Seeds
2. Whole plant
3. Tissue
4. All of these
If we were to list the traits or characters that the breeders have tried to incorporate into crop plants, the first will be
1. Resistance to pathogens.
2. Increased tolerance to insect pests.
3. Increased tolerance to salinity and drought.
4. Crop yield and improved quality.
Agriculture contributes about _____ of India’s GDP and gives employment to _______ of the population
1. 15%, 18%
2. 33%, 62%
3. 62%, 33%
4. 62%, 70%
Mutation breeding
1. Is the use of induced mutations in plant breeding to develop improved varieties.
2. Can be done only by physical mutagens.
3. Has led to the development of mung bean resistant to yellow mosaic virus (YMV) and
powdery mildew
4. Both 1. and 3.
Before the transfer, plantlets from a tissue culture lab into the field, these plantlets are adapted to tolerate harsh environments outside. This process is called
1. Hardening
2. Suspension
3. Regeneration
4. Heterosis
Haploid culture/Androgenic culture was first developed by
1. Guha and Maheshwari in Datura innoxia.
2. Swaminathan in Datura innoxia.
3. Ramdeo Mishra in Solanum.
4. Venkatraman in Saccharum.
Plants can be made disease resistant through
1. Colchicine treatment
2. X-ray treatment
3. Hormone treatment
4. Breeding with wild relatives
Microbe used for biocontrol of pest butterfly caterpillars is
1. Bacillus thuringiensis.
2. Streptococcus species
3. Trichoderma species
4. Saccharomyces cerevisiae
A biofertilizer is
1. Cyanobacterium Anabaena in cavities of Azolla leaves.
2. Symbiotic association of Azotobacter for fixing atmospheric nitrogen.
3.Farmyard manure.
4.Green manure
Which antibiotic is not produced by a moneran
1. Erythromycin
2. Streptomycin
3. Penicillin
4. Tetramycin
Flocs is
1. Primary sludge produced in sewage treatment.
2.A type of biofortified food.
3. A mesh like structure formed by association of bacteria and fungal filaments in sewage
treatment.
4. The effluent in primary treatment tank obtained during sewage treatment
Identify the set which has all organisms used in biological control of pests
1. | Trichoderma, Nucleopolyhedro virus, Bacillus thuringiensis, Lady Bird (Lady Bug) beetle. |
2. | Dragon flies, Bacillus thuringiensis, Lady Bird, Aphids. |
3. | Lady Bird, Penicillium, Baculovirus, Aspergillus. |
4. | Trichoderma, Aspergillus, Bacillus thuringiensis, Nucleopolyhedro virus. |
Ernest Chain and Howard Florey’s contribution was
1. Discovery of streptokinase.
2. Establishment of potential of penicillin as effective drug.
3. Discovery of DNA sequences.
4. Isolating the bacterial plasmid.
Which of the following in sewage treatment removes suspended solids?
1. Secondary treatment.
2. Primary treatment
3. Sludge treatment
4. Tertiary treatment
Conversion of milk to curd improves its nutritional value by increasing the amount of
1. Vitamin D
2. Vitamin A
3. Vitamin
4. Vitamin E
Arrange the following compounds in the order of leaving group ability
(II)
(1). I>II>III>IV (2). IV>III>I>II
(2). III>II>I>IV (3). II>III>IV>I
Which of the following derivatives of benzene would undergo hydrolysis most readily with aq. KOH?
1. 2.
3. 4.
On warming with and aqueous NaOH, iodoform and sodium succinate are formed. The formula of the compound should be
1. 2.
3. 4. None of these
Identify 'A' in -
1. 2-acetoxybenzoic acid 2. methyl salicylate
3. methyl benzoate 4. 2-methoxy benzoic acid
An amide (A) on hydrolysis gives an amine (B) and an acid (C). B gives carbylamine reaction where as C reduces Tollen's reagent. (A) is
1. 2.
3. 4.
The major product obtained when is reacted with
1. 2.
3. 4.
In cannizzaro's reaction the intermediate that will be the best hydride donor is
1. 2.
3. 4.
The appropriate reagent for the transformation is
1. 2.
3. Both 1. and 2. 4. None of the above
Identify the product (C) in the series
1. 2.
3. 3.
In the reaction
the oxidizing agent can be
1. alkaline 2. acidified
3. benedict's solution 4. All of the above
Benzophenone does not react with
1. 2.
3. HCN 4. all of these
on reaction with followed by the action of soda lime gives only chlorobenzene. The compound is
1. 2.
3. 4.
When propanoic acid is treated with aqueous sodium bicarbonate, is liberated. The 'C' of comes from
1. carboxylic acid group 2. methylene group
3. bicarbonate 4. methyl group
Which of the following acids has the smallest dissociation constant?
1. 2.
3. 4.
can be converted into . The correct sequence of reagents is
1. 2.
3. 4.
Benzoylchloride is prepared from benzoic acid by
1. 2.
3. 4.
Which of the following statements are true about HCOOH?
1. It is stronger acid than
2. It reduces Tollen's reagent
3. It gives CO and on heating with conc.
4. all of these
When acetone is reacted with concentrated then the final product formed is
1. Phorone 2. Mesitylene
3. Mesityl oxide 4. Crotonaldehyde
When glycerol is reacted with oxalic acid at then the final product formed is
1. Formic acid 2. Allyl alcohol
3. Acrolein 4. Acetic Acid
Which carboxylic acid is least reactive towards decarboxylation on heating?
1. 2.
3. 4.
Identify X in-
The end product of the following reaction would be
1. 2.
3. 4.
A para- disubstitude aromatic compound, gives a positive test solution, and on acid hydrolysis yields 1, 4- dihydroxybenzene. The compound is
1. 2.
3. 4.
1. I>II>III>IV 2. I>III>IV>II
3. I>III>II>IV 3. I>II>IV>III
The correct order of increasing reactivity towards acid hydrolysis is
1. 1<2<3 2. 3<1<2
3. 1<3<2 4. 2<1<3
The major product formed would be-
1.
2.
3.
4.
Which of the following is the strongest acid?
1. 2.
3. 4.
Which one of the following compounds will show nitro-acinitro tautomerism?
1.
2.
3.
4.
Which of the following compounds can behaves as electrophile as well as nucleophile?
1. 2.
3. 4. All of these
In the given reaction
[X] will be
(a) (b) Sn /conc. HCl
(b) (d) All of these
Arrange given amines in decreasing order of their basicity :
(a) I>II>III (b) I>III>II
(b) III>II>I (d) II>III>II
In the given reaction
[X] will be
(a) Sn/conc HCl (b) Sn/ conc
(c) Sn/conc (d) Sn /
In the given
[X] will be :
(a) (b)
(d) (d) Hydrazobenzene
In the given reaction :
[X] will be
(a) (b)
(c) (d)
In the given reaction :
[Y] will be
1. 2.
3. 4.
In Gabriel synthesis; halide may be:
1. Benzyl halide 2. Allyl halide
3. Both 1. and 2. 4. Teritary alkyl halide
Which of the following compounds will be soluble in NaOH ?
1. 2.
3. 4.
Which one of the following is known as Hofmann reagent ?
1.
2.
3.
4.
Primary, secondary and tertiary amines can be separated from their mixture by the use of :
1. Oxalyl chloride 2. Benzene sulphonyl chloride
3. p-Toluene sulphonyl chloride 4. All of these
Nitrosamine test is given by :
1. Primary amines
2. Aromatic secondary amine
3. Aliphatic as well as aromatic secondary amines
4. Quaternary ammonium halides
Primary, secondary and tertiary can be distinguish chemically by :
1 2.
3. 4. All of these
Which of the following will NOT react with ?
1. 2.
3. 4.
Aniline does not give coupling reactions at pH < 5 because :
1. Diazonium salt converts into which cannot couple
2. Aniline converts into , which cannot couple
3. Both of (1) and (2)
4. Coupling only takes place in basic medium
In is –
1. 2.
3. 4.
Which of the following curves correctly show the variation of capacitive reactance with frequency n –
1. 2.
3. 4.
The equation of AC voltage is and the A.C. current is I = 10 sin . The average power dissipated is –
1. 150 W 2. 550 W
3. 250 W 4. 1000 W
The voltage time (V-t) graph for triangular wave having peak value is as shown in figure.
The rms value of V in time interval from t = 0 to T/4 is –
1. 2.
3. 4. None of these
In the LCR series circuit, the voltmeter and ammeter readings are –
1. E = 100 volts, I = 2 amp 2. E = 100 volts, I = 5 amp
3. E = 300 volts, I = 2 amp 4. E = 300 volts, I = 5 amp
An inductor Henry, a capacitor and a resistor are connected in series across a source of EMF V = 10 sin (314 t). If resistance is removed from the circuit and the value of inductance is doubled, then the variation of current with time in the new circuit is –
1. 0.52 cos 314 t 2. 0.52 sin 314 t
3. 0.52 sin (314 t +/3) 4. None of these
When 100V D.C. is applied across a solenoid a current of 1A flows in it. When 100V A.C. is applied across the same coil, the current drops to 0.5 A. If the frequency of the A.C. source is 50 Hz the impedance and inductance of the solenoid are –
1. 100 , 0.93 H 2. 200 , 1.0 H
3. 100 , 0.86 H 4. 100 , 0.55 H
Resonance frequency of a circuit is f. If the capacitance is made 4 times the initial value, then the resonance frequency will become :
1. f/2 2. 2f
3. f 4. f/4
The current flowing in a coil is 3 A and the power consumed is 108 W. If the a.c. source is of 120 V, 50 Hz, the resistance of the circuit is :
1. 24 2. 10
3. 12 4. 6
When an AC source of emf e = sin (100 t) is connected across a circuit, the phase difference between the emf e and the current i in the circuit is observed to be as shown in the diagram. If the circuit consists possibly only of R-C or R-L or L-C series, find the relationship between the two elements.
1. 2.
3. 4.
If the readings of are 100 volt each then reading of is-
1. 0 volt 2. 100 volt
3. 200 volt 4. cannot be determined by given information.
A sinusoidal voltage \(V_0 \sin \omega t\) is applied across a series combination of resistance \(R\) and capacitance \(C\). The amplitude of the current in this circuit is:
1. \(\frac{V_0}{\sqrt{R^2+\omega^2 C^2}}\)
2. \(\frac{V_0}{\sqrt{R^2-\omega^2 C^2}}\)
3. \(\frac{V_0}{(R+C \omega)}\)
4. \(\frac{V_0}{\sqrt{R^2+\frac{1}{\omega^2 C^2}}}\)
In the circuit shown in figure, what will be the readings of voltmeter and ammeter ?
1. 800V, 2A 2. 220V, 2.2A
3. 300V, 2A 4. 100V, 2A.
For a LCR series circuit with an A.C. source of angular frequency
1. | circuit will be capacitive if \(\omega>\frac{1}{\sqrt{LC}} \) |
2. | circuit will be inductive if \(\omega=\frac{1}{\sqrt{LC}} \) |
3. | power factor of circuit will be unity if capacitive reactance equals inductive reactance |
4. | current will be leading voltage if \(\omega>\frac{1}{\sqrt{LC}} \) |
In the adjoining A.C. circuit the voltmeter whose reading will be zero at resonance
1. 2.
3. 4.
The peak value of an alternating e.m.f. E given by is 10 volt and its frequency is 50 Hz. At a time ts the instantaneous value of the e.m.f. is-
1. 10 volt 2. volt
3. 5 volt 4. 1 volt
If = 200 volt, R = 25 ohm, L= 0.1 H and F and the frequency is variable, then the current at f = 0 and will be respectively
1. 0A, 8A 2. 8A, 0A
3. 8A, 8A 4. 0A, 0A
A uniform but time-varying magnetic field B (t) exists in a circular region of radius a and is directed into the plane of the paper, as shown. The magnitude of the induced electric field at point P at a distance r from the centre of the circular region :
1. is zero 2. decreases as 1/r
3. increases as r 4. decreases as
In the figure shown a square loop PQRS of side ‘a’ and resistance ‘r’ is placed in near an infinitely long wire carrying a constant current I. The sides PQ and RS are parallel to the wire. The wire and the loop are in the same plane. The loop is rotated by 180° about an axis parallel to the long wire and passing through the mid points of the side QR and PS. The total amount of charge which passes through any point of the loop during rotation is-
1. 2.
3. 4. cannot be found because time of rotation not given.
A coil having number of turns N and cross-sectional area A is rotated in a uniform magnetic field B with an angular velocity . The maximum value of the emf induced in it is –
1. 2.
3. 4.
A series combination of inductance (L) and resistance (R) is connected to a battery of emf E. The final value of current depends on –
1. L and R 2. E and R
3. E and L 4. E, L, and R
A current-carrying wire is placed below a coil in its plane, with current flowing as shown. If the current increases –
1. no current will be induced in the coil
2. an anticlockwise current will be induced in the coil
3. a clockwise current will be induced in the coil
4. the current induced in the coil will be first anticlockwise and then clockwise
A thin semi-circular conducting ring of radius R is falling with its plane vertical in a horizontal magnetic induction (see figure). At the position MNQ the speed of the ring is v and the potential difference developed across the ring is
1. zero
2. Bv/2 and M is at higher potential
3.RBv and Q is at higher potential
4. 2RBv and Q is at higher potential
A wooden stick of length 3l is rotated about an end with constant angular velocity in a uniform magnetic field B perpendicular to the plane of motion. If the upper one third of its length is coated with copper, the potential difference across the whole length of the stick is –
1. 2.
3. 4.
A superconducting loop of radius \(R\) has self-inductance \(L\). A uniform and constant magnetic field \(B\) is applied perpendicular to the plane of the loop. Initially current in this loop is zero. The loop is rotated by \(180^\circ\). The current in the loop after rotation is equal to:
1. zero
2. \(
\frac{B \pi \mathrm{R}^2}{L}
\)
3. \( \frac{2 B \pi \mathrm{R}^2}{L}
\)
4. \(\frac{B \pi \mathrm{R}^2}{2 L}\)
Current in just after closing the switch and in steady state respectively will be
1. 0,0 2.
3. 4. cannot be determined
A semicircular wire of radius R is rotated with constant angular velocity about an axis passing through one end and perpendicular to the plane of the wire. There is a uniform magnetic field of strength B. The induced emf between the ends is –
1. 2.
3. is variable 4. none of these
The current in an L – R circuit builds up to of its steady state value in 4 seconds. The time constant of this circuit is
1. 2.
3. 4.
There is a uniform magnetic field B normal to the xy plane. A conductor ABC has length parallel to the x- axis, and length parallel to the y-axis. ABC moves in the xy plane with velocity The potential difference between A and C is proportional to
1. 2.
3. 4.
An emf of 15 volt is applied in a circuit containing 5 henry inductance and 10 ohm resistance. The ratio of the currents at time t = and at t = 1 second is-
1. 2.
3. 4.
A conducting rod is rotated in a plane perpendicular to a uniform magnetic field with constant angular velocity. The correct graph between the induced emf \((e)\) across the rod and time \((t)\) is:
1. | 2. | ||
3. | 4. |
A conducting square loop of side L and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. A magnetic induction B, constant in time and space, pointing perpendicular and into the plane of the loop exists everywhere, see figure. The current induced in the loop is
1. BLv/R clockwise 2. BLv/R anticlockwise
3. 2 BLv/R anticlockwise 4. zero.
Rate of increment of energy in an inductor with time in series LR circuit getting charge with battery of emf E is best represented by – [inductor has initially zero current]
1. 2.
3. 4.
A small square loop of wire of side l is placed inside a large square loop of wire of side L . The loops are coplanar and their centers coincide. The mutual inductance of the system is proportional to
1. 2.
3. 4.
The sun light strikes the upper atmosphere of earth with intensity 1.38 Kw/. The peak value of electric field at that point will be- (in kilovolt/meter)
1. 2.04 2. 4.08
3. 8.16 4. 1.02
Which of the following is the correct statement for the refractive index μ :
1. μ = 2. μ = sin i/sin r
3. 4. Both 2. and 3.
The magnetic field B and electric field E in an electomagnetic wave are :
1. in same direction but with phase difference of 90°
2. in same direction but with zero phase difference
3. mutually perpendicular but with 0° phase difference
4. mutually perpendicular but with 90° phase difference
What is the magnitude of momentum that is contained in a unit volume for an electromagnetic wave :
1. 2.
3. 4.
The ratio of the pressure exerted by electromagnetic waves on reflecting surface and the absorbing surface will be -
1. 2 : 1 2. 1 : 2
3. 3 : 1 4. 1 : 3
The value of total energy density of electromagnetic waves in vacuum will be :
1. 2.
3. 4.
Intensity of electromagnetic wave will be :
1. 2.
3. 4.
The magnitude of electric field at 10 meter distance apart from a source is 100 volt/meter in electromagnetic waves being emitted by a point source. The electric field at point 20 meter from the source will be :
1. 100 volt/m 2. 200 volt/m
3. 50 volt/m 4. 25 volt/m
Which of the following are not electromagnetic waves ?
1. Cosmic-rays 2. -rays
3. -rays 4. Both (1) and (3)
If the velocity of light in free space is then value of wavelength of electromagnetic wave of frequency will be:
The large vessels for growing microbes on an industrial scale are called
1. Petri dish
2. digestors
3. biogas vessel
4. fermentors
BOD of waste water is estimated by measuring the amount of
1. total organic matter
2. biodegradable organic matter
3. oxygen evolution
4. oxygen consumption
Big holes in Swiss cheese are made by a
1. machine
2. bacterium that produces methane gas
3. bacterium producing a large amount of carbon dioxide
4. fungus that releases a lot of gases during its metabolic activities