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Biology cell mcq

1. Who discovered cell in 1665? a) Robert Hook b) Robert Crook c) David Thomson d) Marie Francois Ans. a) 2. Name an Organelle ...

Thursday, 9 January 2020

Ray optics mcq

Ray optics mcq


  1. The speed of light is_______ in vacuum.

    1. 3 x 105 m/s 
    2. 3 x 108 m/s 
    3. 3 x 108 km/s 
    4. 3 x 106 m/s 
  2. The wavelength of the visible light is ________.

    1. 4 x 10(-7) to 8 x 10(-7) m 
    2. 4 x 107 to 8 x 107 m 
    3. 4 x 10(-7) to 8 x 10(-7) Å 
    4. 4 x 107 to 8 x 107 Å 
  3. We can see objects because of_______

    1. reflection 
    2. refraction 
    3. transmission 
    4. diffraction
  4. The image formed by a convex mirror is always________

    1. real 
    2. enlarged
    3. virtual and enlarged 
    4. diminished
  5. As you move an object away from a convex mirror, its image becomes_____ and moves towards______

    1. smaller, infinity 
    2. smaller, focus
    3. enlarged, infinity 
    4. enlarged, focus
  6. For a spherical mirror, ______ is true.

    1. f = 2R 
    2. R = 2f
    3. fR = 2 
    4. fR = 1/2
  7. The mirror formula is ________.

    1. 1/u - 1/v = 1/f 
    2. 1/f + 1/u = 1/v
    3. f = uv/(u+v) 
    4. f = (u+v)/uv
  8. For a plane mirror, magnification (m)=________

    1. 0 
    2. 1
    3. ± 1 
    4. ≤ 0
  9. Magnification for convex mirror is ________.

    1. always positive 
    2. always negative
    3. sometimes positive 
    4. 1
  10. The image formed by a concave lens is ________.

    1. always real and enlarged 
    2. always real and diminished
    3. always virtual and enlarged 
    4. always virtual and diminished
  11. The lens formula is ________.

    1. 1/f = 1/u + 1/v 
    2. 1/f = 1/u - 1/v
    3. 1/f = 1/v - 1/u 
    4. 1/f + 1/v = u
  12. 1 diopter = ________.

    1. 1 m 
    2. 1 m(-1)
    3. 1 cm 
    4. 1 cm(-1)
  13. Which of the following is a true statement?

    1. The power of a lens is always positive. 
    2. The power of a lens is always negative.
    3. The power of a convex lens is positive. 
    4. The power of a concave lens is positive.
  14. Image formed by a concave mirror is erect and enlarged.What is the position of the object?

    1. Between focus F and the center of curvature 
    2. At the center of curvature
    3. Beyond the center of curvature 
    4. Between pole and the focus
  15. If the focal length of a spherical mirror is 40 cm, then its radius of curvature is _______ cm.

    1. 80 
    2. 20
    3. 10 
    4. 5
  16. The velocity of light in vacuum is _______ ms(-1)

    1. 3 x 106 
    2. 3 x 108
    3. 3 x 10 12 
    4. 3 x 1015
  17. If the angle of incidence, θi = 0°, the angle of reflection, θr = ________.

    1.  
    2. 90°
    3. 180° 
    4. 45°
  18. No matter how far is the object from the mirror, the image of the object appears erect. The mirror is ________.

    1. concave 
    2. convex
    3. either concave or convex 
    4. none of these
  19. A boy is standing at a distance of 2 m in front of a plane mirror.The distance between the boy and his image is ________ m.

    1. 4 
    2. 3
    3. 2 
    4. 1
  20. The image formed by a concave mirror is real, inverted and of the same size as that of the object.The position of the object should be ________.

    1. beyond the center of curvature of mirror 
    2. between the center of curvature and the focus
    3. at the center of curvature of the mirror 
    4. at the focus
  21. Which of the following has the highest refractive index?

    1. Glass 
    2. Water
    3. Pearl 
    4. Diamond
  22. Absolute refractive index of any medium is always _______.

    1. 1 
    2. > 1
    3. < 1 
    4. 0
  23. The image formed by a plane mirror is ______.

    1. real 
    2. diminished
    3. enlarged 
    4. laterally inverted
  24. The incident ray passing through the focus(F) of a mirror ______ after reflection.

    1. passes through C 
    2. passes through F
    3. becomes parallel to the principal axis 
    4. passes through the pole
  25. The incident ray passing through the center of curvature(C) of a mirror ______ after reflection.

    1. passes through C 
    2. passes through F
    3. passes through the pole 
    4. becomes parallel to the principal axis
  26. The incident ray parallel to the principal axis of a mirror ______ after reflection.

    1. passes through C 
    2. passes through F
    3. passes through the pole 
    4. reverts back in the opposite direction
  27. According to the sign convention, the distance of object...

    1. is always positive 
    2. is always negative
    3. may be positive or negative 
    4. is equal to object height
  28. According to the sign convention, the distance of image...

    1. is always positive 
    2. is always negative
    3. may be positive or negative 
    4. is equal to image height
  29. The refractive index of a denser medium with respect to a rarer medium is...

    1. 1 
    2. greater than 1
    3. smaller than 1 
    4. negative
  30. The refractive index of a rarer medium with respect to a denser medium is...

    1. 1 
    2. greater than 1
    3. smaller than 1 
    4. negative
  31. Total internal reflection will occur if the angle of reflection is...

    1. 45° 
    2. 60°
    3. 90° 
    4. 99°
  32. Magnification for ______ image is always ______.

    1. real, positive 
    2. real, negative
    3. virtual, negative 
    4. any, negative
  33. If magnification is +1.5, the image is______.

    1. erect
    2. diminished
    3. real
    4. inverted




ANSWERS TO MCQs:


(1) B (2) A (3) A (4) D (5) B (6) B (7) C (8) B (9) A (10) D (11) C (12) B (13) C (14) D (15) A (16) B (17) A (18) B (19) A (20) C (21) D (22) B (23) D (24) C (25) A (26) B (27) B (28) C (29) B (30) C (31) D (32) B (33) A

Optics mcq


1.   Focal length of plane mirror is
         a. At infinity
         b. Zero
         c. Negative
         d. None of these
2.   Image formed by plane mirror is
         a. Real and erect
         b. Real and inverted
         c. Virtual and erect
         d. Virtual and inverted
3.   A concave mirror gives real, inverted and same size image if the object is placed
         a. At F
         b. At infinity
         c. At C
         d. Beyond C
4.   Power of the lens is -40, its focal length is
         a. 4m
         b. -40m
         c. -0.25m
         d. -25m
5.   A concave mirror gives virtual, refract and enlarged image of the object but image of smaller size than the size of the object is
         a. At infinity
         b. Between F and C
         c. Between P and F
         d. At E
6.   In optics an object which has higher refractive index is called
         a. Optically rarer
         b. Optically denser
         c. Optical density
         d. Refractive index
7.   The optical phenomena, twinkling of stars, is due to
         a. Atmospheric reflection
         b. Total reflection
         c. Atmospheric refraction
         d. Total refraction
8.   Convex lens focus a real, point sized image at focus, the object is placed
         a. At focus
         b. Between F and 2F
         c. At infinity
         d. At 2F
9.   The unit of power of lens is
         a. Metre
         b. Centimeter
         c. Diopter
         d. M-1
10.   The radius of curvature of a mirror is 20cm the focal length is
         a. 20cm
         b. 10cm
         c. 40cm
         d. 5cm
Answers
1.   A
2.   C
3.   C
4.   C
5.   C
6.   B
7.   C
8.   C
9.   C
10. B


ELECTRICITY MCQ QUESTIONS




1.  What is the rate of flow of electric charges called?
(a)  Electric potential
(b)  electric conductance
(c)  Electric current
(d)  none of these
2.  Which of the following is the SI Unit of Electric Current?
(a)  ohm
(b)  ampere
(c)  volt
(d)  faraday
3.  Which instrument is used for measuring electric potential?
(a)  Ammeter
(b)  galvanometer
(c)  voltmeter
(d)  potentiometer
4.  When one unit electric charge moves from one point to another point in an electric circuit, then the amount of work done in joules is known as?
(a)  Electric current
(b)  electric resistance
(c)  electric conductance
(d)  potential difference
5.  The hindrance presented by material of conductor to the smooth passing of electric current is known as:
(a)  Resistance
(b)  Conductance
(c)  Inductance
(d)  None of these
6.  The resistance of a conductor is directly proportional to:
(a)  Its area of cross-section
(b)  density
(c)  melting point
(d)  length
7.  The purpose of a rheostat is:
(a)  Increase the magnitude of current only
(b)  Decrease the magnitude of current only
(c)  Increase or decrease the magnitude of current
(d)  None of these
8.  Point to be kept in mind for verification of Ohm’s Law is:
(a)  Ammeter and voltmeter should be connected in series
(b)  Ammeter should be connected in series and voltmeter in parallel
(c)  Ammeter should be connected in parallel and voltmeter in series
(d)  Ammeter and voltmeter should be connected in parallel
9.  When a 40V battery is connected across an unknown resistor there is a current of 100 mA in the circuit. Find the value of the resistance of the resister:
(a)  5000 Ω
(b)  800 Ω
(c)  0.8 Ω
(d)  none of these
10.  A battery of 6V is connected in series with resisters of 0.1 ohm , 0.15 ohm,0.2 ohm,0.25 ohm and 6 ohm. How much current would flow through the 0.3 ohm resistor?
(a)  0.895A
(b)  2.22A
(c)  1A
(d)  none of these
11.  A fuse wire is inserted in a?
(a)  . Live wire
(b)  . In the neutral wire
(c)  . In the earth wire
(d)  . May be connected in any line.

12.How the charge will flow?
(a)By heating them
(b)By applying potential difference
(c)Both
(d)None of the above
13.If length of a conductor and it’s radius is increased twice, how the resistance will change?
(a)Resistance will remain unchanged
(b)Resistance increases twice
(c)Resistance will become half
(d)Resistance will increase 4 times
14. The potential difference applied is directly proportional to current only if
(a)Always
(b)Never
(c)Sometimes
(d)When temperature is constant
15.Equivalent resistance of 4 4Ω resistances in parallel is
(a)4Ω
(b)1Ω
(c)2Ω
(d)16Ω
16. Which of the following conditions represent more resistance at constant temp?
(a)The red line
(b)The yellow line
(c)Both are equal
(d)Can’t be said
17. There is a wire of length l and cross section A. Which of the following have least Resistance?
(a)Length doubled, Area halved
(b)Length tripled, Area doubled
(c)Length halved, Area doubled
(d)The original Wire
18.On which of the following parameters specific resistance depends?
(a)Length of wire
(b)Area of wire
(c)Current passing through it
(d)Temperature
19. A resistor of length l is connected to a battery and current I is flowing through it. If it is divided into 3 parts by length, and all are having same cross sectional area are connected in series with the same battery, the current flowing through them will be?
(a)I/3
(b)3I
(c)I
(d)3I/2
20.Two resistances R1 and R2 are connected with a cell in parallel. Find the ratio of current flowing through R1to the current flowing through R2.
(a)R1:R2
(b)R2:R1
(c)1:1
Data not sufficient
21. Which of the following statement is true regarding Ammeter and Voltmeter?
(a)Ammeter is connected in series with the required device, Voltmeter in Parallel
(b)Both Ammeter and Voltmeter are connected in series with required device
The Voltmeter is connected in series with the device, Ammeter in parallel
(d)They can be connected in any way.

Tuesday, 7 January 2020

रासायनिक यौगिक और उनके सामान्य नाम


    

1. आम नाम: बेकिंग पाउडर

 रासायनिक यौगिक: सोडियम बाइकार्बोनेट

 रासायनिक सूत्र: NaHCO3

 2. आम नाम: ब्लू विट्रिओल

 रासायनिक यौगिक: कॉपर सल्फेट

 रासायनिक सूत्र: CuSO4।  XH2O

 3. आम नाम: ब्लीचिंग पाउडर

 रासायनिक यौगिक: कैल्शियम ऑक्सीक्लोराइड

 रासायनिक सूत्र: CaOCL2

 4. आम नाम: क्लोरोफॉर्म

 रासायनिक यौगिक: ट्राइक्लोरो मिथेन

 रासायनिक सूत्र: CHCl3

 5. आम नाम: चाक (संगमरमर)

 रासायनिक यौगिक: कैल्शियम कार्बोनेट

 रासायनिक सूत्र: CaCo3

 6. आम नाम: कास्टिक पोटाश

 रासायनिक यौगिक: पोटेशियम हाइड्रॉक्साइड

 रासायनिक सूत्र: KOH

 7. आम नाम: कास्टिक सोडा

 रासायनिक यौगिक: सोडियम हाइड्रॉक्साइड

 रासायनिक सूत्र: NaOH

 8. आम नाम: सूखी बर्फ

 रासायनिक यौगिक: ठोस कार्बोंडाईऑक्साइड

 रासायनिक सूत्र: CO2

 9. आम नाम: एप्सोम

 रासायनिक यौगिक: मैग्नीशियम सल्फेट

 रासायनिक सूत्र: MgSo4

 10. आम नाम: जिप्सम

 रासायनिक यौगिक: कैल्शियम सल्फेट

 रासायनिक सूत्र: CaSo4।  2H2O

 11. आम नाम: ग्रीन विट्रियल

 रासायनिक यौगिक: लौह सल्फेट

 रासायनिक सूत्र: FeSo4

 12. आम नाम: भारी पानी

 रासायनिक यौगिक: ड्यूटेरियम ऑक्साइड

 रासायनिक सूत्र: D2O

 13. आम नाम: सिरका

 रासायनिक यौगिक: एसिटिक एसिड

 रासायनिक सूत्र: CH3COOH

 14. आम नाम: वॉशिंग सोडा

 रासायनिक यौगिक: सोडियम कार्बोनेट

 रासायनिक सूत्र: Na2CO3

 15. कॉमन नेम्स: स्लेक्ड लाइम

 रासायनिक यौगिक: कैल्शियम हाइड्रॉक्साइड

 रासायनिक सूत्र: सीए (ओएच) 2

 16. आम नाम: पोटाश एलम

 रासायनिक यौगिक: पोटेशियम एल्यूमीनियम सल्फेट

 रासायनिक सूत्र: KAl (SO₄) ₂ · 12H .O

 17. आम नाम: त्वरित चूना

 रासायनिक यौगिक: कैल्शियम ऑक्साइड

 रासायनिक सूत्र: CaO

 18. आम नाम: प्लास्टर ऑफ पेरिस

 रासायनिक यौगिक: कैल्शियम सल्फेट

 रासायनिक सूत्र: CaSO4।  1/2 एच 2 ओ

 19. आम नाम: मोहर का नमक

 रासायनिक यौगिक: अमोनियम फेरस सल्फेट

 रासायनिक सूत्र: (NH4) 2Fe (SO4) 2 · 6H2O

 20. आम नाम: सफेद विट्रियल

 रासायनिक यौगिक: जिंक सल्फेट

 रासायनिक सूत्र: ZnSo4.7H2O

 21. आम नाम: मार्श गैस

 रासायनिक यौगिक: मिथेन

 रासायनिक सूत्र: सीएच 4

 22. आम नाम: मैग्नेशिया

 रासायनिक यौगिक: मैग्नीशियम ऑक्साइड

 रासायनिक सूत्र: MgO

 23. आम नाम: लाफिंग गैस

 रासायनिक यौगिक: नाइट्रस ऑक्साइड

 रासायनिक सूत्र: N2O

 24. आम नाम: सिंदूर

 रासायनिक यौगिक: मरक्यूरिक सल्फाइड

 रासायनिक सूत्र: HgS

 25. आम नाम: चीनी

 रासायनिक यौगिक: सुक्रोज

 रासायनिक सूत्र: C12H22O11

 26. सामान्य नाम: T.N.T.

 रासायनिक यौगिक: ट्रिनिट्रोटोलुइन

 रासायनिक सूत्र: C7H5N3O6

 27. आम नाम: रेत

 रासायनिक यौगिक: सिलिकॉन ऑक्साइड

 रासायनिक सूत्र: SiO2

CHEMICAL FORMULAS AND THEIR COMMON NAMES


       

1. Common Names: Baking Powder
Chemical Compounds: Sodium Bicarbonate
Chemical Formula: NaHCO3
2. Common Names: Blue Vitriol
Chemical Compounds: Copper Sulphate
Chemical Formula: CuSO4. XH2O
3. Common Names: Bleaching Powder
Chemical Compounds: Calcium Oxychloride
Chemical Formula: CaOCL2
4. Common Names: Chloroform
Chemical Compounds: Trichloro Methane
Chemical Formula: CHCl3
5. Common Names: Chalk (Marble)
Chemical Compounds: Calcium Carbonate
Chemical Formula: CaCo3
6. Common Names: Caustic Potash
Chemical Compounds: Potassium Hydroxide
Chemical Formula: KOH
7. Common Names: Caustic Soda
Chemical Compounds: Sodium Hydroxide
Chemical Formula: NaOH
8. Common Names: Dry Ice
Chemical Compounds: Solid Carbondioxide
Chemical Formula: CO2
9. Common Names: Epsom
Chemical Compounds: Magnesium Sulphate
Chemical Formula: MgSo4
10. Common Names: Gypsum
Chemical Compounds: Calcium Sulphate
Chemical Formula: CaSo4. 2H2O
11. Common Names: Green Vitriol
Chemical Compounds: Ferrous Sulphate
Chemical Formula: FeSo4
12. Common Names: Heavy Water
Chemical Compounds: Deuterium Oxide
Chemical Formula: D2O
13. Common Names: Vinegar
Chemical Compounds: Acetic Acid
Chemical Formula: CH3COOH
14. Common Names: Washing Soda
Chemical Compounds: Sodium Carbonate
Chemical Formula: Na2CO3
15. Common Names: Slaked Lime
Chemical Compounds: Calcium Hydroxide
Chemical Formula: Ca(OH)2
16. Common Names: Potash Alum
Chemical Compounds: Potassium Aluminium Sulphate
Chemical Formula: KAl(SO₄)₂·12H₂O
17. Common Names: Quick Lime
Chemical Compounds: Calcium Oxide
Chemical Formula: CaO
18. Common Names: Plaster of Paris
Chemical Compounds: Calcium Sulphate
Chemical Formula: CaSO4. 1/2 H2O
19. Common Names: Mohr's Salt
Chemical Compounds: Ammonium Ferrous Sulphate
Chemical Formula: (NH4)2Fe(SO4)2·6H2O
20. Common Names: White Vitriol
Chemical Compounds: Zinc Sulphate
Chemical Formula: ZnSo4.7H2O
21. Common Names: Marsh Gas
Chemical Compounds: Methane
Chemical Formula: CH4
22. Common Names: Magnesia
Chemical Compounds: Magnesium Oxide
Chemical Formula: MgO
23. Common Names: Laughing Gas
Chemical Compounds: Nitrous Oxide
Chemical Formula: N2O
24. Common Names: Vermelium
Chemical Compounds: Mercuric Sulphide
Chemical Formula: HgS
25. Common Names: Sugar
Chemical Compounds: Sucrose
Chemical Formula: C12H22O11
26. Common Names: T.N.T.
Chemical Compounds: Trinitrotoluene
Chemical Formula: C7H5N3O6
27. Common Names: Sand
Chemical Compounds: Silicon Oxide
Chemical Formula: SiO2

Wednesday, 1 January 2020

Monotremes


Egg-laying Mammals

Echidna
Echidna. Photo by Dr. Lloyd Glenn Ingles © 2001 California Academy of Sciences.
 
There are only five living monotreme species: the duck-billed platypus and four species of echidna (also known as spiny anteaters). All of them are found only in Australia and New Guinea. Monotremes are not a very diverse group today, and there has not been much fossil information known until rather recently.
In some ways, monotremes are very primitive for mammals because, like reptiles and birds, they lay eggs rather than having live birth. In a number of other respects, monotremes are rather derived, having highly modified snouts or beaks, and modern adult monotremes have no teeth. Like other mammals, however, monotremes have a single bone in their lower jaw, three middle ear bones, high metabolic rates, hair, and they produce milk to nourish the young.
Monotremes are one of the three main groups of living mammals, along with placentals and marsupials. The monotremes are typified by structural differences in their brains, jaws, digestive tract, reproductive tract, and other body parts compared to the more common mammalian types. 
Order: Monotremata
Scientific name: Monotremata
Class: Mammalia
Phylum: Chordata