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from , Kolkata
Subject :NSO    Class : Class 4

Ans 1:

neha garg from Lancer convent school, new Delhi
Class : Class 4
B

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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:

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

Ans 2:

Bhargavi from Bethany, Bangalore
Class : Class 1
The answer is B because the question says that he HEATED both the metals (most metals expand on heating) and Y has expanded more than X

Ans 3:

Anahita Baruah from DPS Bangalore East, Bengaluru
Class : Class 2
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 4:

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

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:

aditya parlewar from St. Xaviers High school , Nagpur
Class : Class 3

Ans 7:

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

Ans 8:

Pratham Dave from GNS, Bangalore
Class : Class 7
B is the answer to this question

Ans 9:

Ashmi Narkar from The Shishukunj International School, Jhalaria Campus, Indore
Class : Class 8
B because if Y expands and X contracts, X will be a lot smaller than Y. Here, both are almost the same size.

Ans 10:

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

Ans 11:

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

Ans 12: (Master Answer)

Admin from revisewise, Noida
Class : Class 1

Ans 13:

aditya parlewar from St. Xaviers High school , Nagpur
Class : Class 3
b

Ans 14:

Arav Gupta from Delhi Public School Gurgaon, Gurgaon
Class : Class 7
D or B not sure.

Ans 15:

Soumyaraj Roy from Kendriya Vidyalaya , Thiruvananthapuram
Class : Class 7
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 16:

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

Ans 17:

ayush from kv no.1 dhanbad, Dhanbad
Class : Class 10
B

Ans 18:

Ishaan singhal from CCWS, Jaipur
Class : Class 3
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 19:

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

Ans 20:

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

Ans 21:

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

Ans 22:

Aarnav Grover from Anand Niketan Shilaj, Ahmedabad
Class : Class 9
d

Ans 23:

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

Ans 24:

shubhavi Dhondge from NPS, Banagalore
Class : Class 8
B is the answer

Ans 25:

Saipriya from Sankara, Chennai
Class : Class 8
B m kids because Y is only curled much . dont get angry

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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:

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

Ans 2:

Vartika Agarwal from Phoenix world school, Pune
Class : Class 9
I will go mad with the number of wrong answers in this website.. answer should be a. For example when a spoon has to be electroplated with copper, copper is ALWAYS ON ANODE and the spoon is ALWAYS ON CATHODE. Why different logic is used here?

Ans 3:

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

Ans 4:

Amrit Biswas from INDUSVALLEY PUBLIC SCHOOL, Noida
Class : Class 10
What is the correct answer A or C ???????

Ans 5:

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

Ans 6:

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

Ans 7:

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

Ans 8:

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

Ans 9:

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

Ans 10:

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

Ans 11:

Akshara from NPS, Bengaluru
Class : Class 8
Yes it should be A .

Ans 12:

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

Ans 13:

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

Ans 14:

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

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:

Amol Athawale from WoodRidge High, aurangabad
Class : Class 6
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 17:

Prabhav Kaushik from DPS Noida, Noida
Class : Class 8

Ans 18:

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

Ans 19:

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

Ans 20:

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

Ans 21:

Paarth Vashistha from Kunskapsskolan Gurgaon , Gurgaon
Class : Class 8
A

Ans 22:

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

Ans 23:

Bipasana from KV IIT Kanpur, Kanpur
Class : Class 9
It has to be A.

Ans 24:

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

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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:

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

Ans 2:

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

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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:

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 2:

ARNAV GARG from PRUDENCE SCHOOL, New Delhi
Class : Class 10
c

Ans 3:

Gauri Singh from St. John's School, Marhauli, Varanasi
Class : Class 10
Yes, but in the given figure it is sedimentation

Ans 4:

A Andrew from Lalaji Memorial Omega International School, Chennai
Class : Class 5
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.

Ans 5:

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.

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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:

Soham from Vibgyor high, Pune
Class : Class 8

Ans 2:

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.

Ans 3:

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

Ans 4:

Student from School, City
Class : Class 5

Ans 5:

arnav from the gurukul, Panchkula
Class : Class 5

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