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Aswath Krishna from DPS EAST, Bengaluru
Subject :NSO    Class : Class 6

A potter shapes pots out of clay (Process 1). He then bakes the pots in an oven (Process 2). Which of the following statements is correct?

A Process 1 is a reversible, physical change while process 2 is an irreversible, physical change.
B Process 1 is an irreversible, physical change while process 2 is an irreversible, chemical change.
C Process 1 is a reversible, physical change while process 2 is an irreversible, chemical change.
D None of these.


Is it A or C?

Ans 1:

Aadvik saini from Mvn sector 17, Faridabad
Class : Class 8
answer is a

Ans 2:

D Murari from Indian School of Excellence, Bangalore
Class : Class 9
C,because- it is a chemical change. after baking we can break it into smaller particles but it won't form the same clay, with same properties again

Ans 3:

ATHARV RAHUL MAHAJAN from ST. STEPHENS SCHOOL CHANDIGARH, SAS NAGAR
Class : Class 6
IF WE SHARP A PENCIL IT IS A PHYSICAL IRREVERSIBLE CHANGE .SO,IF WE HEAT A POT IS PHYSICAL IRREVERSIBLE CHANGE. BUT IT COULD HAPPEN THAT THE COMPOSITION OF CLAY MIGHT CHANE BECAUSE OF HEATING AS THE MOLECULES STICK TO EACH OTHER

Ans 4:

Aarush Goyal from D.A.V Pblic school, Sector 14, Faridabad
Class : Class 6
A is the correct answer

Ans 5:

ridhima from mdps, faridabad
Class : Class 6

Ans 6:

Archisman Rout from Podar International School, Powai
Class : Class 7
A is correct because it just turns hard but it is still clay only.And also chemical change doesn't mean that it is irreversible,Chemical change means that the identity of the substance we started with is lost.Here the identity is not lost.So A is correct.

Ans 7:

RUDRAKSH BISWAS from MAYOOR PRIVATE SCHOOL, ABU DHABI
Class : Class 6
It really should be A

Ans 8:

Tanishtha from DPS, Greater Noida
Class : Class 7
c is the correct answer

Ans 9:

Rasha Ranjan from DPS NOIDA , Vaishali
Class : Class 6
Yes ,Because chemical means change in the properties but there is no change .The answer is A

Ans 10:

Advay Das from Delhi Public School, Gurgaon
Class : Class 4

Ans 11:

Anika Saha from New Town School, KOLKATA
Class : Class 6
The answer is A.

Ans 12:

VIJAYA SREYAS B from NARAYANA OLYMPIAD SCHOOL KUKATPALLY, HYDERABAD
Class : Class 6
C because we can get clay back from a wet pot by smashing it,but once it heats up, it dries the clay and makes it stone hard.

Ans 13:

Vidula Malkar from DPYA High school, Mumbai
Class : Class 7
a is the correct answer because chemical composition dose not change

Ans 14:

Arnesh from dps, delhi
Class : Class 6
It should be A

Ans 15:

Sohan Choudhury from Delhi Public School Electronic City Bengaluru, Bengaluru
Class : Class 6
on heating, the clay pot doesn't turn into stone,right?it doesn't change composition once heated , it is still clay ! answer is "A"

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Vivek Gulavani from Innisfree House School, Bengaluru
Subject :NSO    Class : Class 7

A student took an iron rod and a wooden rod and wrapped each of them in a piece of paper. These were then heated as shown. It was found that the paper around the iron rod does not burn whereas the one around the wooden rod catches fire. It is because


A Candle, in case of iron rod, is nearer to the paper
B Wood being a bad conductor of heat, takes away all the heat
C Iron being a good conductor of heat, conducts away the heat given to the paper
D Paper, in first case, is thicker.


could someone please explain the answer

Ans 1:

Aarnavi Mann from Scholars rosary Sr. Sec. School, Rohtak
Class : Class 8

Ans 2:

Aadvik saini from Mvn sector 17, Faridabad
Class : Class 8
ans is option C

Ans 3:

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

Ans 4:

Parshti Bajpai from Modern Public School, ALWAR
Class : Class 7
Please explain it to me.

Ans 5:

saikrishna from bharatiya vidhya bhavans public school, Hyderabad
Class : Class 9
can someone explain why?

Ans 6:

Lakshya Vijeta from Afgji, New Delhi
Class : Class 7
Option D is correct. I dont know why. Please explain

Ans 7:

Aksh Swarnkar from National Center for Excellence CVR, Bangalore
Class : Class 7

Ans 8:

Praveen Rai from Lotus Valley International School, Noida
Class : Class 7

Ans 9:

Harshdeep roy from Bhavans School , Nagpur
Class : Class 7
answer is option c

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Pradhyumna from J S S Public School, Bengaluru
Subject :NSO    Class : Class 4

Ans 1:

Sandipta Bhattacharjee from Sri Ram Narayan Singh Memorial High School, Kolkata
Class : Class 5
Not kerwa its kewra. It is an extract that is distilled from the flower of the Pandanus plant. Kewra water is very similar to rosewater. It is used to flavour South Asian cuisine.

Ans 2:

Sandipta Bhattacharjee from Sri Ram Narayan Singh Memorial High School, Kolkata
Class : Class 5
jk kj;

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SANAJY GOPAL BHARTARIYA from ST. FIDELIS COLLEGE, LUCKNOW
Subject :NSO    Class : Class 6

Ans 1:

Aarush Goyal from D.A.V Pblic school, Sector 14, Faridabad
Class : Class 6
it will be maximum near the ground

Ans 2:

VIJAYA SREYAS B from NARAYANA OLYMPIAD SCHOOL KUKATPALLY, HYDERABAD
Class : Class 6
As it goes up,kinetic energy decreases due to gravity while potential energy increases with height. As it comes down, kinetic energy increases due to gravity while potential energy decreases.

Post Your Answer

SANAJY GOPAL BHARTARIYA from ST. FIDELIS COLLEGE, LUCKNOW
Subject :NSO    Class : Class 6

Ans 1:

Aarush Goyal from D.A.V Pblic school, Sector 14, Faridabad
Class : Class 6
it will be maximum near the ground

Post Your Answer

Prasuk Jain from Modern Delhi Public School, Faridabad
Subject :NSO    Class : Class 7

Saurabh burned two different fibres X and Y in order to identify them. X smelt like burning paper while Y smelt like burning hair. Which of the following options correctly identifies the two fibres?


Ans 1:

Aksh singh from The asian school, Dehradun
Class : Class 7

Ans 2:

Ishaan Roy from Sri Chaitanya Techno School, Bengaluru
Class : Class 10

Ans 3: (Master Answer)

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

Post Your Answer

Pulkit Gupta from Maxfort School, New Delhi
Subject :NSO    Class : Class 6

Ans 1:

Mihika Hivarekar from Global Indian International School, Pune
Class : Class 7
CHILL PPL CHILL

Ans 2:

niuv from meridian, Hyderabad
Class : Class 6
ANS IS D

Ans 3:

pranavramesh from sri chaitanya techno school, Chennai
Class : Class 6
sof the answer is ddd so many times i am really fed up of your wrong answers and that is really very shamful on you.

Ans 4:

Ashwak from Cambridge, Jalandhar
Class : Class 8
Explain this dumb question and an even dumber answer " Master Answer"

Ans 5:

Aditya Sai Kedarisetty from Sri Kumarans childrens Academy DKS, Bangalore
Class : Class 7
The answer is 'D' option, 'All of the above'. It is so because Air is not visible because it neither absorbs nor reflects light, it transmits whole of light. Dust particles in air is visible as they reflect light. Air is almost transparent substance. It is not dust to be visibile. It is air, it is completely transparent.

Ans 6:

Hari Govind from Delhi Public School Chandigarh , Chandigarh
Class : Class 6
THE ANSWER IS D

Ans 7:

Tanishtha from DPS, Greater Noida
Class : Class 7
ans is d

Ans 8:

Sharmi Chowdhury from G.D Birla Centre For Education , Kolkata
Class : Class 7
Answer is d

Ans 9:

ARAMINTA SAHA from VIBGYOR HIGH BALEWADI, PUNE
Class : Class 6
ans is d because it is transparent which allows light to pass, it doesn't observe light but transmits all light

Ans 10:

Mitra Maiti from Techno India Group Public School, Bolpur Prantik
Class : Class 6
It is true that air is a perfectly transparent object. It neither absorbs nor reflects light. It transmits whole of light. So, all the options are correct and answer is D.

Ans 11:

Parth Kaushish from MDPS, Faridabad
Class : Class 6
its D come on two total mistakes in one test

Ans 12:

Aadvik saini from Mvn sector 17, Faridabad
Class : Class 8
i agree with d

Ans 13:

Aditya Sai Kedarisetty from Sri Kumarans childrens Academy DKS, Bangalore
Class : Class 7
@ashwak control your language

Ans 14:

Devdarsh hero from HOLY GRACE, Mala
Class : Class 6
ans is D

Ans 15:

ARUNAV from DPS VINDHYANAGAR, VINDHYANAGAR
Class : Class 10
these days sof olympiad trainer has gone mad. in one test, i got 4 perfectly wrong question . and now this . this adds up to fivei do not know what is the problemans should be ddddddddd!!!!!

Ans 16:

Tanishtha from DPS, Greater Noida
Class : Class 7
ans is d

Ans 17:

Thejaswini from Rajagiri, Chennai
Class : Class 7

Ans 18:

HARSHAL KUTE from cambridge school buldhana, Buldhana
Class : Class 6
ans is d

Ans 19:

Aarush Laddha from NCFE, bengaluru
Class : Class 6
Answer is D as air it neither absorbs or reflects light,its almost transparent,it transmits the whole of light.

Ans 20:

Shruti Rajshree from NPS Indiranagar, Bengaluru
Class : Class 3
answer is B as given in the answers. there is a solution too

Ans 21:

kpks14 from RIMT World School, Chandigarh
Class : Class 7
d is the answer but the trainer is showing b as answer air reflects light that is why the sky is blue

Ans 22:

Siddharth from DPS, Jodhpur
Class : Class 9
The correct answer should be option D, All of these

Ans 23:

Anika Saha from New Town School, KOLKATA
Class : Class 6
ANS IS D

Ans 24:

khushi Joshi from Svkm , Mumbai
Class : Class 10
Ans is D as air is all of the above

Ans 25:

Pratheek from Null, Null
Class : Class 4
Option D. All of the above.

Ans 26:

Ishayu Mukherjee from Don Bosco Park Circus, Kolkata
Class : Class 6
The answer is wrong. The correct answer is D

Ans 27: (Master Answer)

Admin from revisewise, Noida
Class : Class 1

Ans 28:

Ashwak from Cambridge, Jalandhar
Class : Class 8
What in the freaking world . I am surprised that these dumb idiots can even host international and national olympiads . Even a 5 year old could get the answer right . I won't be surprised if they give the answer 22 of the question 2 2 . I am telling you we are wasting money on these damn question papers

Ans 29:

Utkarsh Chakravarty from Pinnacle High International School, Mumbai
Class : Class 6
I agree with everyone is Satwik because air trasparent it neither reflects nor absorbs light and trasmits whole of light So ans is D

Ans 30:

Arsh from Lahs, Gwalior
Class : Class 3
ans is d sof !!!!!!!!!!!!! ans is d

Ans 31:

Advik from DPS Patna, Patna
Class : Class 4
its got to be ddddd!!

Ans 32:

Aarnav Grover from Anand Niketan Shilaj, Ahmedabad
Class : Class 9
I think its D not B

Ans 33:

satwik patnaik from DPS Rourkela, Rourkela
Class : Class 7
And is b

Ans 34:

Bhabani Prasad from Narayan School, Kolkata
Class : Class 6
D is the ans as air is matter and is very transparent.

Ans 35:

Naisha from Brilliant public school b, Bilaspur
Class : Class 8
D

Ans 36:

Utkarsh Chakravarty from Pinnacle High International School, Mumbai
Class : Class 6
i mean except Satwik

Ans 37:

arnav santosh shinde from new english school , landewadi
Class : Class 4
ANS IS D

Ans 38:

Ayush Chauhan from Modern Public School, Bhiwadi
Class : Class 9
Answer is D

Ans 39:

Ashwak from Cambridge, Jalandhar
Class : Class 8
Answer is D

Ans 40:

Aarav Garg from DPS Greater Noida, Greater Noida
Class : Class 7
It should be d but they are telling its b.

Ans 41:

Mihika Hivarekar from Global Indian International School, Pune
Class : Class 7

Ans 42:

Videh Jain from Bluebells School International, Delhi
Class : Class 6
d is the ans

Ans 43:

Karthik from Euro, Bengaluru
Class : Class 7
ans is d

Ans 44:

Agrim Jai from Modern Bharakhamba, Delhi
Class : Class 7
D

Ans 45:

Pratheek from Null, Null
Class : Class 4
Option D. All of the above.

Ans 46:

AJAY LAHOTI from SPRINGDALES DUBAI, Dubai
Class : Class 6
I should be d

Post Your Answer

Swati from Ryan, Bengaluru
Subject :NSO    Class : Class 8

Ans 1:

Harsh Kant from Gyan Ganga Educational Academy, Raipur
Class : Class 9

Ans 2:

sk from psbb millennium school, Chennai
Class : Class 9

Ans 3:

N Sankar Narahari from Madhavakripa English Nursery and Higher Primary School, Manipal
Class : Class 7
answer is b

Ans 4:

Gokul Warrier M from SRI KUMARANS MALLASANDRA, BANGALORE
Class : Class 9

Ans 5:

N Sankar Narahari from Madhavakripa English Nursery and Higher Primary School, Manipal
Class : Class 7
everybody just copy and paste it, can anyone explain in an easier way

Ans 6:

Sumedha Mishra from xyz, School, Pune
Class : Class 8

Ans 7: (Master Answer)

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

Ans 8:

chepz from abc school, pandikkad
Class : Class 10
The common error is to think that pressure at 0.4h above the surface of the reservoir of mercury is 0.4 times the atmospheric pressure. The pressure at p is caused by the weight of mercury above point P. Thus preesure at P is equal to : 0.6x 100000 = 60000 Pa

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Mihir Arora from dpsg, ghaziabad
Subject :NSO    Class : Class 3

Ans 1:

Malav patel from Navrachana school sama , Vadodara
Class : Class 4
A is the correct answer as 1 and 2 are correct

Ans 2: (Master Answer)

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

Post Your Answer

Harshita.B from Narayana e techno school, Poonamalle
Subject :NSO    Class : Class 3

Ans 1:

Thaneesha from Radcliffe School, Kharghar
Class : Class 7
Y...I DONT UNDERSTAND SOOOOO....................TELL MEH!!

Ans 2:

Ashwak from Cambridge, Jalandhar
Class : Class 8
I too

Ans 3:

Karangat house from Navy Children School, Payyannur
Class : Class 3

Ans 4: (Master Answer)

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

Ans 5:

Arnav Yadav from Delhi Public School Rohini ,New Delhi, New Delhi
Class : Class 6
obviusly it will be d

Ans 6:

SHAUNAK from St Xaviers School, HAZARIBAG
Class : Class 3
The correct answer is D [friction].

Post Your Answer

X Y
(A) Wool Silk
(B) Cotton Rayon
(C) Cotton Silk
(D) Silk Wool