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Anvesh from navy Children school, mumbai
Subject :NSO    Class : Class 10

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
The correct answer is D.

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Soham De from DPS, Nerul, Mumbai
Subject :NSO    Class : Class 5

Ans 1:

Srishti Rani from DBMS ENGLISH SCHOOL, Jamshedpur
Class : Class 5
cONFUSED IN d AND B

Ans 2:

arya navare from Saint ursula school, kankavli
Class : Class 5

Ans 3:

Arav Singh from Jyoti Niketan School, Azamgarh
Class : Class 6
b

Ans 4:

Abhisyant M Baruah from DPS Bangalore East, Bengaluru
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:

Hitanshi Behera from Loyola School , Bhubaneswar
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:

shubhavi Dhondge from NPS, Banagalore
Class : Class 5
B is the answer

Ans 7:

Hitanshi Behera from Loyola School , Bhubaneswar
Class : Class 4
DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD

Ans 8:

Sumit Singhal from Cambridge Court World School, JAIPUR
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:

Rehaan Barodawala from Goldcrest High Vashi, Navi Mumbai
Class : Class 5

Ans 10:

Shrija Roy from Ryan international school icse, mumbai
Class : Class 6

Ans 11:

Sanskriti Nagar from Rose Bud Academy, khagaria
Class : Class 5
B is the correct answer

Ans 12:

Aarnav Grover from Calorx olive international school, Ahmedabad
Class : Class 5
d

Ans 13:

Prajjwal Dey from MLZS Wakad, PUNE
Class : Class 5

Ans 14:

Arnav kaul from Chirec, Hyderabad
Class : Class 5

Ans 15:

ayush from kv no.1 dhanbad, Dhanbad
Class : Class 8
B

Ans 16:

Pratham Dave from GNS, Bangalore
Class : Class 6
B is the answer to this question

Ans 17:

Satvik Agrawal from Delhi Public School, bhopal
Class : Class 5
D or B? please vote

Ans 18:

Ashmi Narkar from VIBGYOR HIGH , Airoli, Navi Mumbai, NAVI MUMBAI
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:

Shivangi from St. Michael's High School, Patna
Class : Class 5
C is the correct answer

Ans 20:

Fareeha siddiqua from Janki Devi public school , Mumbai
Class : Class 5
b as Y expands more

Ans 21:

SHUBHANI LAKHERA from ANN MARY SCHOOL, Dehradun
Class : Class 5
B is the right answer

Ans 22:

Soumyaraj Roy from Kendriya Vidyalaya , Thiruvananthapuram
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:

Hitanshi Behera from Loyola School , Bhubaneswar
Class : Class 4
sof does not reply that is why we are confused

Ans 24:

Gauri Singh from St Johns School Marhauli, Varanasi
Class : Class 8
The answer should be opt.B

Ans 25:

Hitanshi Behera from Loyola School , Bhubaneswar
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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Kshitij Gupta from St Kabir din, Ahmedabad
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:

from Bhandari Public School, KHANDWA
Class : Class 9
The correct answer is AAAAAAA

Ans 2:

Riya Singhani from BVB vidhyashram, jaipur
Class : Class 8
WWWWRRRROOOONNNNNNNNNNGGGGGGGGGGGGGGGGG

Ans 3:

Abhay Agarwal from St Francis School, Ghaziabad
Class : Class 9

Ans 4:

Tanush from presidency east, Bangalore
Class : Class 5
And for this question must be A

Ans 5:

Anshuman D from MVM, Hyderabad
Class : Class 9
Yes the answer is A

Ans 6:

Sounak halder from Kendriya Vidyalaya Cossipore, kolkata
Class : Class 8
the answer will be 'A'

Ans 7:

Amol Athawale from WoodRidge High, aurangabad
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:

Nishtha Neelabh from Lok Puram Public School, Thane West
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:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 10
thus answer is a

Ans 10:

tamojit das from techno India Group Public School , Chinsura
Class : Class 8
cation(Zn2 ) must be deposited to the cathode.

Ans 11:

Dhars from DPS EAST Bangalore , Bengaluru
Class : Class 10
the answer is wrong.....it should be a

Ans 12:

aditya arora from Heritage Experiential Learning School, gurugram
Class : Class 8
it should be a

Ans 13:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 10
my apologies for the previous explanation answer is : C

Ans 14:

bipasana from KV IIT Kanpur, Kanpur
Class : Class 8
It has to be A.

Ans 15:

Raghav Tyagi from birla vidya niketan, new delhi
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:

Chaitanya L K from SKCHEC, bangalore
Class : Class 8
Yes it is A

Ans 17:

Abhay Agarwal from St Francis School, Ghaziabad
Class : Class 9
answer A

Ans 18:

Chatresh ramasai gudi from Bgsnps , Bangalore
Class : Class 8
Answer is a

Ans 19:

Bhagyesh Kamal from DPS, Mumbai
Class : Class 8
answer is a

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H KRITHIK from kendriya vidyalaya, chennai
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:

Varsha from Nps banashankari Bangalore, Bangalore
Class : Class 3
B

Ans 2:

Dishen dharmenra patel from Anand niketan to the satellite , Ahmedabad
Class : Class 3

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from , Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Medha Bhutani from Christ Academy, Bengaluru
Class : Class 9
ans is c

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from , Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Sriyansh from Surabhi , Hosapete
Class : Class 9
Plug key is also a type of switch.

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Raghav Mittal from DAV Public School, ludhiana
Subject :NSO    Class : Class 5

Ans 1:

ARNAV GARG from PRUDENCE SCHOOL, New Delhi
Class : Class 8
c

Ans 2:

Shivangi from St. Michael's High School, Patna
Class : Class 5
Ya, filtration can also remove insoluble impurities but in this case sedimentation and decanation is more appropriate answer.

Ans 3:

Gauri Singh from St. John's School, Marhauli, Varanasi
Class : Class 8
Yes, but in the given figure it is sedimentation

Ans 4:

Mallika Gupta from NPS indiranagar, Bangalore
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:

A Andriya from Lalaji Memorial Omega International School, Chennai
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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from , Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Medha Bhutani from Christ Academy, Bengaluru
Class : Class 9
every single sound has its own secondary waves, so the correct option must be option C.

Ans 2:

RAHUL S ROY from ST.XAVIERS HIGH SCHOOL,VAPI, VAPI,GUJARAT
Class : Class 7
correct option is c

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Ethel shiju from National Public School Indiranagar, Bangalore
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:

arnav from the gurukul, Panchkula
Class : Class 5

Ans 2:

Yash Bindal from Global Indian International School, Singapore
Class : Class 9

Ans 3:

Student from School, City
Class : Class 8

Ans 4:

Bhuvanesh Singla from SCTS, Bengaluru
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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Ethel shiju from National Public School Indiranagar, Bangalore
Subject :NSO    Class : Class 8

Ans 1:

Anshuman D from MVM, Hyderabad
Class : Class 9
Supposed to be only ABecause mustard is a non leguminous plantEven it can be rotated with soyabean

Ans 2:

S V Harini from Vailankanni public school , Krishnagiri
Class : Class 8
Think in the way of leguminous crops

Ans 3:

Triguna from Kendriya Vidyalaya No.1 Salt Lake, Kolkata
Class : Class 8
Why so? In both the cases soybean is present.

Ans 4:

Pradanya from KV IIT, Chennai
Class : Class 3
yeah right Triguna!!! in both cases soybean is present? why so?

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