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Dhruva Rojekar from Bombayscottishschool , Mumbai
Subject :NSO    Class : Class 7

Ans 1:

Ritwic Verma from The Shri Ram School Moulsari, New Delhi
Class : Class 10
Let’s study the given diagrams showing the cross-section of two flowers carefully: Flower X shows Sepals, Petals and Pistil. There is no Stamen. Flower Y shows Sepals, Petals, Stamens and Pistil. Pistil is the “female” part of a flower, as it produces seeds. Stamen is the “male” part of a flower, as it produces pollen. Now, let’s check the given statements, and find out which ones are correct: (i) Both flowers will produce female gametes. ----- Correct. Since both flowers have Pistil, they both can produce female gametes, or seeds. (ii) Flower X is a female flower and flower Y is a bisexual flower. ----- Correct. Flower X only has Pistil, so it is a female flower. Flower Y has both Stamen and Pistil, so it is a bisexual flower. (iii) Self pollination can take place in both flowers. ----- Incorrect. Since only flower Y has both Stamen and Pistil, self pollination can take place on flower Y only. Only Statements (i) and (ii) are correct, so the right answer is Option C

Ans 2:

Akshay Jha from DPS NERUL, Navi Mumbai
Class : Class 7
The answer should be (i) only as we can clearly see anthers on the side of flower X, but it can't self-pollinate because the anther is a lower altitude than the stigma, hence the stigma cannot receive the pollen grains. So, I still think the answer should be (i).

Ans 3: (Master Answer)

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

Ans 4:

Sherlock Holmes from Baker Street, London
Class : Class 9
Hi! I had the same doubt in mind, but I found the same picture on google which was much more clearer. Even in this picture you can see anthers on the side of the pistil. Thus, the answer should actually be (i) and (iii). But that is not there in the options. Take Care and Hope You Understand :) Darsh Kedia, NSO International Rank 1 and 3

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Devansh Sachdeva from Blooming Vale Public School, Kotdwara
Subject :NSO    Class : Class 5

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Devansh Sachdeva from Blooming Vale Public School, Kotdwara
Subject :NSO    Class : Class 5

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Devansh Sachdeva from Blooming Vale Public School, Kotdwara
Subject :NSO    Class : Class 5

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Devansh Sachdeva from Blooming Vale Public School, Kotdwara
Subject :NSO    Class : Class 5

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naman from dps noida noida, Noida
Subject :NSO    Class : Class 3

Ans 1: (Master Answer)

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

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SANTANU DAS from KENDRIYA VIDYALAYA-I, AFS KALAIKUNDA, Kharagpur
Subject :NSO    Class : Class 8

Ans 1:

Aakarshak Swaraj from Podar international school , Surat , Surat
Class : Class 7
explain the answer please

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pinki kashyap from kids r kids, Chandigarh
Subject :NSO    Class : Class 6

Ans 1:

Advaith m from New horizon public school, Bangalore
Class : Class 4
Wrong option pls change it only Q should come

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pinki kashyap from kids r kids, Chandigarh
Subject :NSO    Class : Class 6

Ans 1:

Shomili from Global Indian International School, Singapore
Class : Class 9
Because making of milk to curd is a chemical change and not physical change as :- A new substance is formed, It is irreversible and permanent, It's chemical components are changed, There is energy loss while making it.

Ans 2:

khushi Joshi from Svkm , Mumbai
Class : Class 10
The answer is C

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pinki kashyap from kids r kids, Chandigarh
Subject :NSO    Class : Class 6

Ans 1:

Rabhya Agarwal from Amity noida, Delhi
Class : Class 7
c is the correct answer as it only shows repulsion property of magnets

Ans 2:

Kaustav Bhowal from Julien Day School, Kolkata
Class : Class 10
The option should be the correct one as the magnet may not rotate due to opposite poles of the magnets. So , it is not necessary for it to rotate in all conditions. So, I think option B is the appropriate answer.

Ans 3:

khushi Joshi from Svkm , Mumbai
Class : Class 10
Only a magnet can attract a compass needle. A magnetic material cannot attract it. Then why not B?

Ans 4:

Diva SINHA from Ralli International School , Ghaziabad
Class : Class 6

Ans 5:

Arin Gupta from DELHI PUBLIC SCHOOL, Karnal
Class : Class 6
FIRST I ALSO DO SAME OPTION THEN I UNDERSTAND THAT IF WE BRING BAR MAGNET NEAR TO IT TO PROVE THAT THIS IS A MAGNET IT WILL ALSO SHOW SOME REPULSION OR ATTRACTION SO THIS IS THE REASON IT ROTATES

Ans 6:

Ojas Patil from Vikhe Patil Memorial School Pune, Pune
Class : Class 7
sorry c is correct

Ans 7:

Puneet Arora from ,
Class : Class 5
Option B is the answer, because if magnet is brought close to the compass, the needle points towards the magnet.

Ans 8:

JUGAAJYOTI DASH from Doon International School, Bhubaneswar
Class : Class 9
The option C indicates repulsion.

Ans 9:

Parth Gupta from Presidium Gurgaon, Gurgaon
Class : Class 8
The answer should be CA) Any magnetic material can also be attracted by a strong magnet(incorrect)B) A magnetic material can also cause the compass needle to move as the needle is a magnet and the needle will move towards it (the needle is very light to cause movement but it will also move towards the object and hence incorrect )C) The question asked what CONFIRMS that an object is a magnet or not . If the 2 like poles are facing each other the object will rotate and then will attract to the other magnet . This will confirm that it is a magnet . If it had not been a magnet then it would directly be attracted to the magnet without rotating . Yes it is not necessary for it to rotate but the question says that what confirms , if the object rotates before being attracted to a magnet then it is a magnet and if it does not rotate before being attracted to magnet it can either be a magnet or not be a magnet (therefore it confirms that it is a magnet)D) If an object gets attracted to both poles of a magnet then it is a magnetic material but it confirms that it is not a magnet . Every magnet has 2 poles the north pole and the south pole , similar poles repel each other and different poles attract each other . If the object had been a magnet then it would have been attracted to only one of the pole and would have repelled the other . Only magnetic materials attract both the poles .

Ans 10:

niuv from meridian, Hyderabad
Class : Class 6
B is the correct answer

Ans 11:

PARNIKA SINGH from GYAN GANGA EDUCATION ACADEMY, RAIPUR
Class : Class 10
Ans B should be the correct answer. Magnet may rotate or may not it will depend upon which pole is close to the other magnet

Ans 12:

Kushal from Chirec, Hyderabad
Class : Class 7

Ans 13:

Kushal from Chirec, Hyderabad
Class : Class 7

Ans 14:

student from school, city
Class : Class 10
The answer is C as it is the only option that somehow results in repulsion while others don't.

Ans 15:

Pragya Mahajan from BCM Arya Model Sr Sec School, Ludhiana
Class : Class 8
no', the ans. should be d

Ans 16:

Ojas Patil from Vikhe Patil Memorial School Pune, Pune
Class : Class 7
d

Ans 17:

Ajit kumar from centre point, NAGPUR
Class : Class 4
Ans.c as even a magnetic material will attract the compass needle. Only a magnet will repel another magnet and rotate before being attracted to the other magnet.

Ans 18:

Kushal from Chirec, Hyderabad
Class : Class 7

Ans 19:

Aarav Gupta from Cambridge International School, Jalandhar
Class : Class 6
both option b and c are the correct options as a magnet repels the needle of the compass if the pole of the magnet is a like pole. If the magnet turns around to stick to the another magnet then it means that it turns so that unlike poles face each other and the mgnets stick to each other

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