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Subject :NSO    Class : Class 10

Ans 1: (Master Answer)

Class : Class 1
The correct answer is D.

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5
cONFUSED IN d AND B

Ans 2:

Class : Class 5

Ans 3:

Class : Class 6
b

Ans 4:

Class : Class 7
All metal expands on heating. Here metal Y expands more which leads to curling of both X and Y. B is the correct option.

Ans 5:

Class : Class 4
iron-nickel alloy notable for its lack of expansion or contraction with temperature changes. hence all metals do NOT expand

Ans 6:

Class : Class 5
B is the answer

Ans 7:

Class : Class 4
DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD

Ans 8:

Class : Class 7
as if we will contract metal x so it is not neccessery that y will contract if we contract metal y x has to be conyracted with it ans should be a

Ans 9:

Class : Class 5

Ans 10:

Class : Class 6

Ans 11:

Class : Class 5
B is the correct answer

Ans 12:

Class : Class 5
d

Ans 13:

Class : Class 5

Ans 14:

Class : Class 5

Ans 15:

Class : Class 8
B

Ans 16:

Class : Class 6
B is the answer to this question

Ans 17:

Class : Class 5
D or B? please vote

Ans 18:

Class : Class 5
B because if Y expands and X contracts, X will be a lot smaller than Y. Here, both are almost the same size.

Ans 19:

Class : Class 5
C is the correct answer

Ans 20:

Class : Class 5
b as Y expands more

Ans 21:

Class : Class 5
B is the right answer

Ans 22:

Class : Class 6
Sumit Singhal , this is a bimetallic metal . Here , the two metals cannot go away from each other . So here , if y expands than x will also expand , and if x expands than y will also expand . I am getting confusion between A and B .

Ans 23:

Class : Class 4
sof does not reply that is why we are confused

Ans 24:

Class : Class 8
The answer should be opt.B

Ans 25:

Class : Class 4
ans should be D as if metal x contracts and metal y expands then the 2 metals will bend inward an as an ellusion we see that y is longer than x

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Subject :NSO    Class : Class 8

The diagram shows a beaker containing a solution of zinc sulphate and two carbon electrodes. A battery is placed next to it. In order that the electrode P be plated with zinc,


A P must be connected to S and Q to R
B P must be connected to Q and S to R
C P must be connected to R and Q to S
D P and Q must be connected to R.


The answer would be a as znso4 wold breakdown into zn 2and so42-ions .the zn 2 would be attracted towards cathode(negative terminal) so p would be attached to negative terminal and therefore the answer is a.

Ans 1:

Class : Class 9
The correct answer is AAAAAAA

Ans 2:

Class : Class 8
WWWWRRRROOOONNNNNNNNNNGGGGGGGGGGGGGGGGG

Ans 3:

Class : Class 9

Ans 4:

Class : Class 5
And for this question must be A

Ans 5:

Class : Class 9
Yes the answer is A

Ans 6:

Class : Class 8
the answer will be 'A'

Ans 7:

Class : Class 8
i do feel that correct answer is A.as P has to be electroplated ,it must be on cathode(-ve).so,correct is =A

Ans 8:

Class : Class 6
answer should be A, as hydrogen is not released at cathode if the other cation is Zinc or below in the electrochemical series

Ans 9:

Class : Class 10
thus answer is a

Ans 10:

Class : Class 8
cation(Zn2 ) must be deposited to the cathode.

Ans 11:

Class : Class 10
the answer is wrong.....it should be a

Ans 12:

Class : Class 8
it should be a

Ans 13:

Class : Class 10
my apologies for the previous explanation answer is : C

Ans 14:

Class : Class 8
It has to be A.

Ans 15:

Class : Class 10
In reactivity series hydrogen is below zinc and is less reactive than zinc. As hydrogen below zinc therefore will reduce more and earlier than zinc , hence will go to cathode and zinc will reduced or deposit at anode. therefore P will be connected to R and Q to S.hence ans is :C

Ans 16:

Class : Class 8
Yes it is A

Ans 17:

Class : Class 9
answer A

Ans 18:

Class : Class 8
Answer is a

Ans 19:

Class : Class 8
answer is a

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Subject :NSO    Class : Class 3

A note is shown here which Ravi has made about different types of house. Unfortunately when he had finished writing, some ink spilt over the page and covered some of the key words.
A wooden house made on a boat is called . It is common in Kashmir and . In areas with heavy rainfall houses are common. are built of snow and are found in very cold countries.
Select the correct sequence of hidden words to complete the note.

A Caravan, Rajasthan, Tent, Igloos
B Houseboat, Kerala, Stilt, Igloos
C Houseboat, Delhi, Kutcha, Igloos
D Tent, Karnataka, Caravan, Igloos


Ans 1:

Class : Class 3
B

Ans 2:

Class : Class 3

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 9
ans is c

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 9
Plug key is also a type of switch.

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 8
c

Ans 2:

Class : Class 5
Ya, filtration can also remove insoluble impurities but in this case sedimentation and decanation is more appropriate answer.

Ans 3:

Class : Class 8
Yes, but in the given figure it is sedimentation

Ans 4:

Class : Class 9
it needs to be sedimentation and decantation because the insoluble material present in the liquid is quite heavy you only perform filtration when the particles float over the surface of the water

Ans 5:

Class : Class 8
sedimentation and decantation is the answer . but filtration can not come because we can see in the picture itself that the particles are big ,that's why sedimentation and decantation . if the particles are small but yet insoluble , then only it is filtration . I hope that you understood.

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 9
every single sound has its own secondary waves, so the correct option must be option C.

Ans 2:

Class : Class 7
correct option is c

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Subject :NSO    Class : Class 8

Read the given statements and select the correct option.
Statement 1 : Phosphorus burns in air at room temperature.
Statement 2 : It is an example of spontaneous combustion.

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.


I say it is option a but they say it is b....But isn’t this definitely due to spontaneous combustion?

Ans 1:

Class : Class 5

Ans 2:

Class : Class 9

Ans 3:

Class : Class 8

Ans 4:

Class : Class 8
Hi, the statement 2 is true but just tells about the type type combustion to which the reaction given in statement belong. it does not tell about actual cause of burning of phosphorus in air at room temperature. the reason for statement 1 is that phosphorus is a highly reactive element that's why burns in air at room temperature.

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Subject :NSO    Class : Class 8

Ans 1:

Class : Class 9
Supposed to be only ABecause mustard is a non leguminous plantEven it can be rotated with soyabean

Ans 2:

Class : Class 8
Think in the way of leguminous crops

Ans 3:

Class : Class 8
Why so? In both the cases soybean is present.

Ans 4:

Class : Class 3
yeah right Triguna!!! in both cases soybean is present? why so?

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