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Thaneesha from Radcliffe School, Kharghar
Subject :NSO    Class : Class 3

Nidhi was asked to draw the shadow of a tumbler formed on the screen
behind it, when it is kept in different manners at the same position and light is shone on it from the same direction. She drew three shadows as shown here.

Read the following statements regarding it and select the INCORRECT ones.
(i) Shadow 1 is formed when the tumbler is kept horizontally.
(ii) Shadow 2 is formed when the tumbler is kept vertically upright.
(iii) Shadow 3 is incorrect because the given tumbler cannot cast a rectangular shadow.

A (i) and (ii) only
B (ii) and (iii) only
C (i) and (iii) only
D None of these


Ans 1:

Aneesh Balaji from BVBARR school, Hyderabad
Class : Class 4
d

Ans 2:

aabhaa from South City International School, kolkata
Class : Class 4

Ans 3:

ANSHUL GAJJAR from PODAR INTERNATIONAL SCHOOL, AHMEDABAD
Class : Class 3
A

Ans 4:

Anagha from DPS BANGALORE NORTH, Bengaluru
Class : Class 3
the third one is wrong

Ans 5:

ANKITA KAKKAR from DPSN, Delhi
Class : Class 3
A

Ans 6:

Devansh from mmvm, Udaipur
Class : Class 5

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Thaneesha from Radcliffe School, Kharghar
Subject :NSO    Class : Class 3

Ans 1:

Samik Praveen from Euro School Airoli, Mumbai
Class : Class 5
But no force is acting on the book

Ans 2:

Jibran Noorshah from Christ Academy, Bengaluru
Class : Class 5
The answer is (B) as the book is under gravitational force that's why the book is on the table.

Ans 3:

aarav m from kumarans, bengaluru
Class : Class 3
B

Ans 4:

Aneesh Balaji from BVBARR school, Hyderabad
Class : Class 4
b is answer

Ans 5:

Jibran Noorshah from Christ Academy, Bengaluru
Class : Class 5
(B)

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Mannat Verma from Vivek High School , Chandigarh
Subject :NSO    Class : Class 5

Ans 1:

Swastik from st marys school, new delhi
Class : Class 6
answer is B because Oil spill is the condition when mineral oil or petroleum oil being carried on a ship gets spilled in the sea due to some reason. This causes death of aquatic organisms. Oil gets coated on feathers of aquatic birds making them unable to fly and to regulate their body temperatures. This causes death of the birds.

Ans 2:

Swastik from st marys school, new delhi
Class : Class 6
sorry by mistake i have written B but the answer is C

Ans 3:

Pratham Dave from GNS, Bangalore
Class : Class 6
C , oil spill

Ans 4:

AREEN from BOLTON, HYDERABAD
Class : Class 6
Ans is C because due to oil spill fishes die because it happens in water. Also, aquatic birds get covered with black coating because of that they can't breathe and they die.

Ans 5:

Tanmay kaushal from ICSE, Mumbai
Class : Class 5

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from DPS North Kolkata, Kolkata
Subject :NSO    Class : Class 4

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from DPS North Kolkata, Kolkata
Subject :NSO    Class : Class 4

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Avantika Raj from Delhi Public School, Bengaluru
Subject :NSO    Class : Class 3

Ans 1:

Mohi from Vibgyor, Bangalore
Class : Class 1
A

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Mannat Verma from Vivek High School , Chandigarh
Subject :NSO    Class : Class 5

Ans 1:

Sankeerth Sunil from Shishya BELM public School, Bangalore
Class : Class 6

Ans 2:

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

Ans 3:

Kaashvi Sharma from Bal Bharati Public School, GRHM, New Delhi
Class : Class 6

Ans 4:

AREEN from BOLTON, HYDERABAD
Class : Class 6
Ans is C because Black Gold is another name for coal.

Ans 5:

Anantjit Chander from Apeejay School, Sector 14, Faridabad, Faridabad
Class : Class 6
In my case, I feel that (A)is a suitable answer. But the correct option is (C). Why?

Ans 6:

Pratham Dave from GNS, Bangalore
Class : Class 6
I prefer option C.

Ans 7:

Maanvik Srivastava from Cornerstone, Hyderabad
Class : Class 5
THE CORRECT ANSWER IS C, BECAUSE BLACK GOLD IS ANOTHER NAME FOR CRUDE OIL OR PETROLEUM .

Ans 8:

Biju Pappachan from Rkc , Raipur
Class : Class 1
Ans 6 is absolutely right. Ans is C.

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vrahulprakaash from Amm, Chennai
Subject :NSO    Class : Class 7

Ans 1:

Ashmita Choudhury from Delhi Public School Noida, Noida
Class : Class 8
Tibia and Fibula(option C.)

Ans 2:

Saanvi from rvk, bengaluru
Class : Class 8
tibia and fibula

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Animesh Jain from DPS, Bengaluru
Subject :NSO    Class : Class 6

Read the given statements and select the correct option.
Statement 1: Groundwater is safe for drinking.
Statement 2: Groundwater is free from soluble impurities.

ABoth statements 1 and 2 are correct and statement 2 is the correct explanation of statement 1.
BBoth statements 1 and 2 are correct but statement 2 is not the correct explanation of statement 1.
CStatement 1 is correct but statement 2 is incorrect.
DBoth statements 1 and 2 are incorrect.


Groundwater is free from soluble impurities is wrong. Ground water is free from suspended impurities but it contains dissolved gases, minerals and salts. Hence answer is C.

Ans 1:

Shourya Mundra from Lotus Valley International School NOIDA, Ghaziabad
Class : Class 8
No ground water has impurities, minerals, gases and some microbes dissolved in it

Ans 2:

Devdarsh hero from HOLY GRACE, Mala
Class : Class 6
groundwater sometimes have heavy metals such as lead and arsenic dissolved in them and hence is always not safe for drinking

Ans 3:

Udit Kankar from Advanced Academy, Indore
Class : Class 6
Groundwater is safe for drinking but is not free of soluble impurities and that is why we boil it, so the correct option is (C)

Ans 4:

Riya Gupta from Birla Divya Jyoti, Siliguri
Class : Class 8
Answer is option'D'. Neither of the statements are correct. And SOF World, Please listen to our comments and reply to it and rectify your mistakes quickly,ASAP. Iam not here to scold you, but trying to advise you. So please, from the heart of all the students who are commenting(including me), rectify all your mistakes ASAP( AS SOON AS POSSIBLE)!!!!!!!!!!!!

Ans 5:

devansh gaurangi from Stella Maris School , Lucknow
Class : Class 8
Some dissolved salts in water is essential for human body and groundwater is free from suspended impurities but it contains soluble things, hence the option is C.

Ans 6:

Ashwak from Cambridge International School, Saudi Al Dera
Class : Class 8
Yes the option C is the correct as groundwater is not always safe

Ans 7:

Sagnik Chatterjee from Delhi Public School, Greater Noida
Class : Class 7
Ground water is not always safe, it can contain soluble impurities like arsenic

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

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