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Subject :NSO    Class : Class 7

Read the given statements and select the correct answer.
Statement 1 : The distance x at which a car can be stopped by applying brakes depends on the initial velocity.
Statement 2 : Mass of the car has no role to play.

A Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
B Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1.
C Statement 1 is true and statement 2 is false.
D Both statements 1 and 2 are false.


mass of the car has role to play due to momentum.

Ans 1:

Class : Class 9
No b is only

Ans 2:

Class : Class 6
Though it looks like mass has no role to play in braking distance, actually coeff of friction (COF) between tyre and road surface has inverse relationship with braking distance. COF depends on normal force due to weight of vehicle and therefore indirectly mass plays a role on braking distance. The correct answer should be C

Ans 3:

Class : Class 4
C is the correct answer. Force is applied to stop the vehicle. The formulae of force is mass * acceleration. Acceleration is final velocity - initial velocity by time. F= M*{(v-u)/t} and its kinetically equation is F=M *[v square - u square/ 2 * distance]. Which ever formula for force has been taken MASS is important. So clearly MASS HAS A ROLE TO PLAY. hence the answer must be C

Ans 4:

Class : Class 8
c is the correct answer and solution is also given in favour of option c. but answer is b

Ans 5:

Class : Class 5

Ans 6:

Class : Class 9

Ans 7:

Class : Class 9
Apropos to the question the mass of the car has a role in the momentum of the car, as Momentum=mv ,therefore option 'C' should be the correct answer.

Ans 8:

Class : Class 9
Yes

Ans 9:

Class : Class 9
C only

Ans 10:

Class : Class 8
C should be the correct answer. Same has been explained in the solution also.

Ans 11:

Class : Class 7
if you read the solution properly it is quite clear that the answer is b

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Subject :NSO    Class : Class 7

Besides the arrangement as shown in the given set-up, what other arrangements must be made to test for the presence of starch in the leaves X and Y ?


A The plant should be destarched first and then used for the experiment.
B The plant should be placed in continuous light for 2-3 days prior to experiment.
C On leaf Y, iodine solution should be put on while leaf X should be used as control without iodine application.
D None of these


I suppose it should be placed in dark for destarching and then in sunlight for testing whether the plant can perform photosynthesis in absence of CO2..

Ans 1:

Class : Class 8
option b

Ans 2:

Class : Class 7
It should be destarched first

Ans 3:

Class : Class 5

Ans 4:

Class : Class 1
option B

Ans 5:

Class : Class 8
Destarching of leaf is a more effective way so option A should be correct

Ans 6:

Class : Class 7
it should be destarched first then keep the setup in sunlight because if we will directly test the presence of starch both the leaves will show blue -black color as there will be starch already present in both of them. So the correct answer should be OPTION A

Ans 7:

Class : Class 7
The plant should be destarched first and then used for the experiment To accurately test for the presence of starch in leaves X and Y.

Ans 8:

Class : Class 8
option b

Ans 9:

Class : Class 8
option b

Ans 10:

Class : Class 8
The leaves should be destarched first, so that there is no presence of starch prior to the experiment in any of the leaves. In that manner, the experiment will be more clear. Therefore, Option A is also a potential answer.

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Subject :NSO    Class : Class 3

Ans 1:

Class : Class 4
B!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Ans 2:

Class : Class 5
all the questions answer is b

Ans 3:

Class : Class 6

Ans 4:

Class : Class 5
b

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5
d is correct answer

Ans 2:

Class : Class 5
D is the answer

Ans 3: (Master Answer)

Class : Class 1

Ans 4:

Class : Class 5

Ans 5:

Class : Class 5
D

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Subject :NSO    Class : Class 5

Refer to the given figure and select the incorrect statement.

(i) S is the coloured circular part of the eye.
(ii) P is the outermost part of eye and it maintains the shape of the eyeball.
(iii) Q is a layer of light sensitive receptors at the back of the eye.
(iv) R carries message from eye to brain.
(v) T is the folded skin above eye which protects eye from dust, durt, etc.

A (i) and (ii) only
B (ii), (iii) and (iv) only
C (i) and (v) only
D (ii), (iv) and (v) only


Ans 1:

Class : Class 3
very tough though the ans is c

Ans 2:

Class : Class 5
tough one,i think the explanation is:S is lens and that part is not colored and t is either eye lids or cornea and neither of them is folded skin.acoording to me

Ans 3:

Class : Class 5
please explain

Ans 4:

Class : Class 6

Ans 5:

Class : Class 4
wrong answer

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 6
What's the Correct answer?

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 6

Ans 2:

Class : Class 6
both answers b and c are not advisable

Ans 3:

Class : Class 6

Ans 4:

Class : Class 6

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 8
After unscrambling the four jumbled words. We get, Sedimentation, Chlorination, Distillation and Filtration. Filtration and Sedimentation are methods of removing insoluble impurities. Distillation is the only option that is used to remove soluble impurities.

Ans 2:

Class : Class 4

Ans 3:

Class : Class 6

Ans 4:

Class : Class 4

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 8
i.e. 6 plus 7 = 13 and 9 plus 7 = 16 . SO, 8 plus 4 is 12.

Ans 2:

Class : Class 8
The pattern followed is 6 7=137 9=16So,8 4=12

Ans 3:

Class : Class 10
option B

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Subject :NSO    Class : Class 8

Air pollutants are harmful to living things. Which of the following is/are their harmful effect(s)?
(i) They form acid rain.
(ii) They cause breathing problems in humans.
(iii) They interfere with photosynthesis in plants.
(iv) They result in the depletion of ozone layer.

A (i) only
B (i) and (ii) only
C (i), (ii) and (iii) only
D (i), (ii), (iii) and (iv)


It is because acid rain is caused by sulphur dioxide and nitrogen dioxide. Breathing problems are caused by various kinds of pollutants. Dust particles interfere with photosynthesis in plants. Chloro-fluoro carbons or CFCs result in the depletion of ozone layer.

Ans 1:

Class : Class 7
Please explain

Ans 2:

Class : Class 9
i dont understand how ?

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