LEARNING SCIENCE

 ....WELCOME TO THE WORLD OF LEARNING SCIENCE....

                   VISIT DAILY FOR NEW UPDATES

                   FROM BASIC TO MASTER LEVEL



Tuesday 30 November 2021

STD-X, HUMAN EYE AND THE COLOURFUL WORLD: Dispersion, MOST IMPORTANT MCQs

1. Which of the following statements is correct regarding the propagation of light of different colours of white light in air?
(a) Red light moves fastest.
(b) Blue light moves faster than green light.
(c) All the colours of the white light move with the same speed.
(d) Yellow light moves with the mean speed as that of the red and the violet light

ANS: All the colours of the white light move with the same speed

 

2.  The splitting of light into its component colours is called-
(a) Spectrum
(b) Dispersion
(c) Tyndall effect
(d) Refraction

 

ANS: Dispersion

 

3.  Dispersion is caused due to _____ of light.

(a) reflection

(b) refraction

(c) scattering

(d) reflection and refraction

 

ANS: refraction

 

4.  The dispersive power of prism depends upon-
(a) The shape of the prism
(b) The material of the prism
(c) The angle of the prism
(d) Height of the prism

 

ANS: the material of the prism

 

5.  The dispersive power will be maximum for-
(a) Flint glass (n=1.65)
(b) Crown glass (n=1.51)
(c) Mixture of glass
(d) None of these

 

ANS: Flint glass

 6.  Sumitra was given two glass prisms. One was made of ordinary glass and other one was of flint glass (Given that refractive index of flint glass is more than that of ordinary glass). She traced the path of rays through both and after observing the diagram and concluded that bending of light for given angle of incidence was

(a) more in the prism made of flint glass

(b) more in the prism made of ordinary glass

(c) same in both the glass prisms

(d) independent of the nature of glass of which the prism was made

 

ANS: more in the prism made of flint glass

6.  Sumitra was given two glass prisms. One was made of ordinary glass and other one was of flint glass (Given that refractive index of flint glass is more than that of ordinary glass). She traced the path of rays through both and after observing the diagram and concluded that bending of light for given angle of incidence was

(a) more in the prism made of flint glass

(b) more in the prism made of ordinary glass

(c) same in both the glass prisms

(d) independent of the nature of glass of which the prism was made

 

ANS: more in the prism made of flint glass

 

7.  For a light travelling in a prism choose the correct option. Inside the prism,

(a) all the colours have same angle of refraction

(b) the colour with more deviation has lesser refractive index

(c) the colour with lesser deviation has more speed

(d) all the colours travel with same speed

 

ANS: the colour with lesser deviation has more speed

 

8.  Which of the colours of visible light has maximum wavelength?
(a) Yellow
(b) Red

(c) Violet

(d) Green

 

ANS: Red

 

STD-VI, STRUCTURE AND FUNCTION OF LIVING ORGANISMS: PLANTS, Objective Question Answers

 1.  Lotion is made from Arnica using its-

(a) seeds

(b) leaf

(c) flower

(d) root

 

ANS: flower

 

2.  Nodes are present on the _____.

(a) stem

(b) leaf

(c) root

(d) fruit

 

ANS: stem

 

3.  A ripened ovary forms a-

 

ANS: Fruit

 

4.  The dried flower buds of the _____ plant is used as spices.

 

ANS: Cloves

 

5.  _____ provide support to the lamina.

 

ANS: veins

 

Monday 29 November 2021

STD-X, HUMAN EYE AND THE COLOURFUL WORLD, Important Questions on Glass Prism, MCQs

1.  A glass prism has-

(a) 5 rectangular surfaces

(b) 4 rectangular surfaces

(c) 2 triangular bases and 3 rectangular surfaces

(d) 2 rectangular surfaces and 3 triangular bases

 

ANS: 2 triangular bases and 3 rectangular surfaces

 

2.  A prism is used to-

(a) pass the light undeviated

(b) deviate a light path by reflection only

(c) refract, reflect or diffract the light depending on experimental condition

(d) deviate a light path by refraction

 

ANS: deviate a light path by refraction

 

3.  The angle between two lateral surfaces of a prism is called as

(a) angle of prism

(b) angle of refraction

(c) reflecting index of the prism

(d) dispersion angle

 

ANS: angle of prism

 

4.  The angle between two plane rectangular refracting surfaces of a prism is called as

(a) refracting angle of the prism

(b) angle of refraction

(c) reflecting angle of the prism

(d) dispersion angle

 

ANS: refracting angle of the prism

 

5.  The angle between the directions of the incident ray and the emergent ray is called-

(a) angle of deviation

(b) angle of refraction

(c) reflecting angle of the prism

(d) dispersion angle

 

ANS: angle of deviation

 

6.  For an equilateral prism the angle of the prism is-

(a) 600

(b) 450

(c) 900

(d) 300

 

ANS: 600

 

7.  How many times refraction occurs when a ray passes through a prism?

(a) 1

(b) 4

(c) 3

(d) 2

 

ANS: 2

 

Sunday 28 November 2021

STD-VI, Electric Current and Circuits, Objective Question-Answers

 

1.  This is used for grinding of wheat-

(a) electric alarm clock

(b) electric flour mill

(c) electric fan

(d) electric oven

 

ANS: electric flour mill

 

2.  Electricity can be generated from _____ sources.

(a) renewable

(b) non-renewable

(c) both renewable and non-renewable

(d) None of these

 

ANS: both renewable and non-renewable

 

3.  Combination of cells form a-

 

ANS: Battery

 

4.  The electric bulb in a torch is kept at the focus of a ______ mirror.

 

ANS: Concave

 

5.  Electric cells produce electricity from ______ stored, and arranged inside them.

 

ANS: Metals and chemicals

Wednesday 24 November 2021

MATH, SIMPLIFICATION

 1.      Simplify the following.

a)      18 + 4 x 6 ÷ 2 – 9

b)      17 x 3 + 81 ÷ 9 – 60

c)      5.3 + 6 x 0.05 – 2.1

d)      28.9 – 20.8 + 3.9

e)      108 ÷ 12 + 46 – 14

f)       1.8 x 2.4 – 2 x 2.1 + 0.12

g)      7 + 7 x 7 ÷ 7 – 7 + 7

h)      16 + 9 – 3 x 12 ÷ 6 – 5

i)        5.3 + 1.5 ÷ 5 x 2 

j)     3 + 3 x 4 ÷ 2

STD-6, CHAPTER-8: STRUCTURE AND FUNCTION OF LIVING ORGANISMS-PLANTS, EXERCISE QAs

 A.     FILL IN THE BLANKS.

1.      Maize, wheat and rice are examples of _____ roots.

Ans: fibrous

2.      Ginger and potato are two examples of modified ______.

Ans: stem

3.      The main function of the ______ is to prepare food for the plant.

Ans: leaf

4.      Banyan is an example of _____ roots.

Ans: prop

5.      ______ is the most attractive, and colourful, part of the plant.

Ans: flower

6.      The leaves of cacti are modified into ______.

Ans: spines

7.      The leaf blade is also known as ______.

Ans: lamina

B.      WRITE TRUE OR FALSE FOR THE FOLLOWING STATEMENTS.

 

1.      All plants possess the tap root system.                                                                     False

2.      The wheat and maize plants have a fibrous root system.                                     True

3.      Cactus plants photosynthesise through their stems.                                             True

4.      Leaves manufacture food for themselves.                                                               False

5.      Flower is meant for the reproduction of the plant.                                               True

6.      The pistil is the female part of a flower.                                                                   True

7.      Stigma and ovary have no role in reproduction of plants.                                    False

8.      Seeds store food for the future plant.                                                                       True

C.      TICK THE CORRECT OPTION.

 

1.      The roots, that are consumed as food, are-

(a)   Onion and sweet potato

(b)   Carrot and onion

(c)    Beet and turnip

(d)   Potato and radish      

      Ans: beet and turnip

2.      The plants manufacture food through the process of-

(a)   Transpiration

(b)   Water conduction

(c)    Photosynthesis

(d)   respiration           

      Ans: photosynthesis

3.      Leaves are attached to the stem at the-  

(a)   Nodes

(b)   Pedicel

(c)    Internode

(d)   stalk      

       Ans: nodes

4.      The total number of whorls, in a flower, is/are–

(a)   One

(b)   Two

(c)    Three

(d)   four                                   

      Ans: four

5.      The reproductive organ, of a plant, is the-

(a)   Flower

(b)   leaf

(c)    seed

(d)   root

      Ans: flower

6.      The part of the flower, that provides protection to the bud, before it blooms-

(a)   sepal

(b)   petals

(c)    stamen

(d)   pistil

      Ans: sepal

D.     ANSWER THE FOLLOWING QUESTIONS IN BRIEF.

 

1.      Name the two main systems of a plant.

Ans: The main systems of a plant are, The Root System and The Shoot System.

2.      Name the different parts of the shoot system.

Ans: The different parts of the shoot system are, stem, branches, flowers, fruits, leaves etc.

3.      Name different types of modified stems.

Ans: Different types of modified stems are,

i) Potato, ginger (food storage stems)

ii) Grapes and Pea tendrils (supporting stems)

iii) Cactus (food preparing stems)

4.      State the role of spines – the modified leaves.

Ans: i) The spines protect the plant from grazing animals.

ii) They also reduce the loss of water during excessively hot climates.

5.      Name the different parts of a flower.

Ans: The different parts of a flower are, pedicel, sepals, petals, stamen and pistil/carpel.

6.      Give the meaning of the term ‘pollination’.

Ans: The process of transfer of pollen grains from the anther to the stigma is called as pollination.

E.      ANSWER THE FOLLOWING QUESTIONS.

 

1.      State the differences between the two main systems of a plant.

Ans: i) The main systems of a plant are, The Root System and The Shoot System.

ii) The root system grows below the ground. But, the shoot system lies above the soil.

2.      Define root system. Give two functions of roots.

Ans: The Root System is that part of the plant which grows below the ground.

Functions of roots:

i) Root fixes the plant to the soil.

ii) Roots absorb water and minerals from the soil

3.      Define shoot system. Give two functions of the stem.

Ans: The part of the plant, which is found above the soil, is known as its shoot system.

Functions of the stem:

i) It keeps the plant straight and upright.

ii) It transports water and minerals, absorbed by the roots, to all parts of the plant.

4.      How is a tap root different from a fibrous root? Give one example of each type.

Ans: i) In tap root system, there is one main root and smaller lateral roots grows out of the main root. Example, Carrot.

ii) In fibrous root system, there is no main root. Several roots grow out from the base of the stem which are almost similar in size. Example, Rice.

5.      What is a leaf? Draw a diagram showing different parts of a leaf.

Ans: The leaf is the green coloured, thin, broad and flat part of a plant.

                           


6.      Name any two types of stem modifications, giving one example for each type.

Ans: i) Stem modified for storing food: Example, In Potato the stem lies underground and it stores food.

ii) Stem modified for manufacturing food: Example, in Cactus the stem is green in colour and prepares food.

7.      Name the two parts of a stamen. State the functions of each of these two parts,

Ans: The two parts of a stamen are: Anther and Filament.

i) The filament provides support to the anther.

ii) The anther produces pollen grains.

8.      What are the functions of a fruit?

Ans: The functions of a fruit are as follows:

i) It protects the seed against injury and other unfavourable climatic conditions.

ii) It helps in the dispersal of seeds.

iii) It stores food material, as in the case of tomato, apple and mango.

iv) Fruits are the edible part of a plant.