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Dheeraj from Sri Sri Ravishankar Vidya Mandir, Bangalore
Subject :NSO    Class : Class 7

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1

Mass is the amount of matter present in an object whereas weight is the force exerted by the gravity on that object.

Now, the weight of an object, W = g X m, where 'g' is Earth's gravitational constant and 'm' is the mass of the object.

The weight of the object will remain constant as long as the mass of that object is not changing since 'g' is constant. However, the weight of an object can still be changed without changing the mass. This can be explained by the following example: Consider a helicopter with a mass, 'm'.

1. If the helicopter is accelerated towards the earth (during landing) with an acceleration equals to 'A' (positive acceleration) then its weight would become, W = (g + A) X m,  and hence, the weight would increase.

2.  If the helicopter is accelerated away from the earth (during take-off) with an acceleration equals to '- A' (negative acceleration) then its weight would become, W = (g - A) X m,  and hence, the weight would decrease.


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Dheeraj from Sri Sri Ravishankar Vidya Mandir, Bangalore
Subject :NSO    Class : Class 7

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1

Mass is the amount of matter present in an object whereas weight is the force exerted by the gravity on that object.

Now, the weight of an object, W = g X m, where 'g' is Earth's gravitational constant and 'm' is the mass of the object.

The weight of the object will remain constant as long as the mass of that object is not changing since 'g' is constant. However, the weight of an object can still be changed without changing the mass. This can be explained by the following example: Consider a helicopter with a mass, 'm'.

1. If the helicopter is accelerated towards the earth (during landing) with an acceleration equals to 'A' (positive acceleration) then its weight would become, W = (g + A) X m,  and hence, the weight would increase.

2.  If the helicopter is accelerated away from the earth (during take-off) with an acceleration equals to '- A' (negative acceleration) then its weight would become, W = (g - A) X m,  and hence, the weight would decrease.


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ansh rai from delhi public school, Bhilai
Subject :NSO    Class : Class 5

Ans 1:

Ishani Gandhi from Lourdes convent school, Surat
Class : Class 6
In the options, it is written wrong because it is mechanical , kinetic energy. Instead of that it should be muscular, kinetic energy

Ans 2:

Shreetej from Pearson public school, Pune
Class : Class 5
Its option (c), mechanical into kinetic

Ans 3:

Pritisha priya from Global Indian International School, Abu Dhabi, Abu Dhabi
Class : Class 7
C.Mechanical, Kinetic

Ans 4:

Poulami Dan from Aditya Academi, Kolkata
Class : Class 5
c

Ans 5:

shaurya aggarwal from scholars rosary senior secondary school, rohtak
Class : Class 9
Mechanical,kinetic

Ans 6:

Tanvi from hh, delhi
Class : Class 7
Hey, anyone wants to explain to me why it is option C?

Ans 7:

Niveideeta Cour from Suncity World School, Gurgaon
Class : Class 5
mechanical into kinectic

Ans 8:

NAISHA JAJWARE from dps noida, noida
Class : Class 5
c

Ans 9:

RISHABH from SUMMER FIELD, GURGAON
Class : Class 5
c

Ans 10:

Saiprajna Panda from Kendriya Vidyalaya, Central University of rajasthan, Kishangarh
Class : Class 5
actually it is written wrong

Ans 11:

shreedhar from the shri ram school, delhi
Class : Class 5
mechanical,kinetic (c)

Ans 12:

Harsh Sobti from the samhita academy, BLR
Class : Class 5

Ans 13:

Pratham Dave from GNS, Bangalore
Class : Class 7
Mechanical into kinetic energy.

Ans 14:

Biju Pappachan from Rkc , Raipur
Class : Class 1
Wanna explain why?

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swagatika from giis, BENGALURU
Subject :NSO    Class : Class 2

Ans 1:

anu from Haralur, Bengaluru
Class : Class 5
D;none of these

Ans 2:

Saatviki from Ryan International School, PUNE
Class : Class 6

Ans 3:

Mahi Chandra from ICON School of Excellence, Bengaluru
Class : Class 3
Mahi from Icon School Of Excellence, BengaluruClass:2D;none of these

Ans 4:

Ipshita from VIBGYOR, Bengaluru
Class : Class 1
The correct answer is d.

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ansh rai from delhi public school, Bhilai
Subject :NSO    Class : Class 5

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1

The correct answer is A.


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Sai srikar from Mitra academy, Bangalore
Subject :NSO    Class : Class 5

Ans 1:

Ashwak from Cambridge, Jalandhar
Class : Class 9
The correct answer is CRhinoceros does not have scales on body while snake, lizard and fish have scales as body covering

Ans 2:

Biju Pappachan from Rkc , Raipur
Class : Class 1
Honestly, if you ask me,I chose snake as the answer because they can peel of their skin while the others can’t. So,Arumolzhi Ramesh I was thinking the same thing. But SOF and most of you guys say that the correct answer is C Rhinoceros as they do not have scales while the other three do. So it must be correct although I did not know lizards had scales on their bodies but as a matter of fact, they do so C must be the correct answer.

Ans 3:

arulmozhi ramesh from Kv, Coimbatore
Class : Class 9
Snakes can peel their skin of while the others can’t

Ans 4:

Nilarka Pahari from Young Horizons School, Kolkata
Class : Class 4
Do lizards really have scales? I don't think so.

Ans 5:

from harvest,
Class : Class 5
The correct answer is CRhinoceros doesn't have scales on their body while snake, lizard and fish have scales as body coveing

Ans 6:

Biju Pappachan from Rkc , Raipur
Class : Class 1
Only this question I got wrong

Ans 7:

Biju Pappachan from Rkc , Raipur
Class : Class 1
Google says lizards have scales.

Ans 8:

Ashwak from Cambridge, Jalandhar
Class : Class 9
The correct answer is CRhinoceros does not have scales on body

Ans 9:

arulmozhi ramesh from Kv, Coimbatore
Class : Class 9

Ans 10:

Shloka Kulkarni from Pawar Public School, Nanded City, Pune
Class : Class 6
Ans is C

Ans 11:

Mohhika Sharma from Delhi Public School Greater Noida, Noida
Class : Class 5
I chose snake too, so Biju Pappachan and Arumolzhi Ramesh, I have the same thought process- it sheds its skin.

Ans 12: (Master Answer)

Admin from revisewise, Noida
Class : Class 1

The correct answer is C.

Rhinoceros does not have scales on body while snake, lizard and fish have scales as body covering.


Ans 13:

Shreeya Mangla from ASN Senior Secondary School, New Delhi
Class : Class 9
Snake, lizard and fish have scales as body covering while rhinoceros doesn't. Hence the correct answer is C

Ans 14:

VISHNU from NARAYANA OLYMPIAD GOPALAPURAM, chennai
Class : Class 5
I ticked the answer as D because fish have gills but the others dont

Ans 15:

Arnesh from DPS Mathura Road , New Delhi
Class : Class 7
Correct is c because rhino does not have scales while others do

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Ayush Das from Griffins international school , Midnapur
Subject :NSO    Class : Class 4

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
To get a complete range of Olympiad Preparation Products (including previous years papers) log on to WWW.mtg.in, content partner for SOF Olympiads. For more details visit our website- details available on www.sofworld.org

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sarag bordoloi from dps numaligarh, golaghat
Subject :NSO    Class : Class 6

Ans 1:

Siddhanth Subramanian from Global Indian International School , Singapore
Class : Class 7

Ans 2:

Souradeepto Das Mandal from Hyderabad Public School, Hyderabad
Class : Class 7
i agree with AYAAN VOHRA the admin is useless and the question is:which of the following is an example of incomplete flower?A) mulberryB) peaC) mustardD) hibiscusi chose (B) but sof said it's(A) and when i checked solutions it said" ." so I searched the forum but everyone(including the"admin")are talking about animals and amoeba.SOF PLS HELP!!!!!!!!!!!!

Ans 3:

Manvi Mundepi from Montfort School Roorkee, Roorkee
Class : Class 9
The backbone or the vertebral column is a long, bony, rod–like structure, which extends from the base of the skull to the lower back. The animals which possess the backbone are called vertebrates and the ones which do not possess it are called invertebrates. Ant, spider, octopus, amoeba and starfish, are all invertebrates.So, the answer is B. Amoeba does not lay eggs. It is an unicellular organism which divide by binary fission.

Ans 4:

arshi.jain4004@gmail.com from ,
Class : Class 1

Ans 5:

Ayan Vohra from Bhavan Vidyalaya , Chandigarh, chandigarh
Class : Class 8
why is everyone talking about animals?! I got a question about plants specifically complete and incomplete flowers. SOF PLEASE HELP ME HELP ME!!!!!!!!! AND THAT ADMIN IS COMPLETELY USELESS

Ans 6:

Souradeepto Das Mandal from Hyderabad Public School, Hyderabad
Class : Class 7
AND THE ANSWER IS AND THE ANSWER IS (A) MULLBERRY as the other three have all the four whorls

Ans 7:

Ayan Vohra from Bhavan Vidyalaya , Chandigarh, chandigarh
Class : Class 8
GIMME GIMME THE ANS

Ans 8:

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

Ans 9:

Ashwak from Cambridge, Jalandhar
Class : Class 9
I agree with ARUNAV

Ans 10: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
The backbone or the vertebral column is a long, bony, rod–like structure, which extends from the base of the skull to the lower back. The animals which possess the backbone are called vertebrates and the ones which do not possess it are called invertebrates. Ant, spider, octopus, amoeba and starfish, are all invertebrates.So, the answer is B. Amoeba does not lay eggs. It is an unicellular organism which divide by binary fission.

Ans 11:

ARUNAV from DPS VINDHYANAGAR, VINDHYANAGAR
Class : Class 10
admin , who are you ? why you do not tell your real name ?

Ans 12:

Bhavtosh Tripathi from Maneckji Cooper Education Trust School, Mumbai
Class : Class 9
amoeba divides itself it does not lay eggs. they all lACK A BACKBONE

Ans 13:

Anshuman Mishra from kv no 3, Bhubaneswar
Class : Class 7
the ans is b

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Nupur Sangwai from Podar International Parbhani, JINTUR
Subject :NSO    Class : Class 10

Ans 1:

Anvesha Dubey from Lodha World School , Dombivali
Class : Class 5
Since the residue obtained was black in colour and we know that only Zinc and Copper on reacting with Iron give a black residue hence the answer is Option D

Ans 2: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
Here, the answer is D. Black residue is obtained in test tubes I and III i.e., iron gets displaced in test tubes I and III. Therefore, metals P and R should be more reactive than iron. No change is observed in test tubes II and IV hence, metals Q and S should be less reactive than iron.

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Gireesha from innocent hearts school jalandhar, Jalandhar
Subject :NSO    Class : Class 10

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
Here, the answer is D. The method used to extract metals from the ore in which they are found depends on their reactivity. For example, reactive metals such as aluminium are extracted by electrolysis, while a less-reactive metal such as iron may be extracted by reduction with carbon or carbon monoxide. The metals low in the reactive series are very less reactive. The oxides of such metals can be reduced to metals by heating alone e.g. mercury is obtained from its ore, cinnabar (HgS), by the process of heating. Metals like iron, zinc, lead etc. occur as sulphides or carbonates in nature. First the ore is converted into its oxide form This is done by either roasting or by calcination. The metal oxide is reduced to metal by using suitable reducing agent such as Carbon.

Ans 2:

Anvesha Dubey from Lodha World School , Dombivali
Class : Class 5
Option D

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