National Science Olympiad Forum By SOF Olympiad Trainer - Page 667

User Forum

Subject :NSO    Class : Class 9

Ans 1:

Class : Class 9
9.6

Ans 2:

Class : Class 9
Can u pls send the method

Ans 3:

Class : Class 10

Post Your Answer

Subject :NSO    Class : Class 9

Ans 1:

Class : Class 9
The answer is 12cm

Ans 2:

Class : Class 10
the answer is 12 cm

Ans 3:

Class : Class 9
The answer is 12cm

Post Your Answer

Subject :NSO    Class : Class 8

Ans 1:

Class : Class 9
glass rod when rubbed with fur, it gives electrons to fur and becomes positively charged

Ans 2:

Class : Class 8
This is wrong, yet nothing has been done to fix it. It has been discovered to be wrong FOUR YEARS ago!

Ans 3:

Class : Class 8
Plastic is unable to be charged.. Wrong answer!

Ans 4:

Class : Class 4

Ans 5:

Class : Class 8
The options given here are a plastic scale,a woollen cloth, an inflated balloon and a COPPER rod, not a GLASS rod. How can the options appear differently for others, since many people here are saying that there is glass rod involved? Also, plastic is an insulator of electricity, so ideally it wouldn't acquire any charge, right? SOF should give a solution to this problem.

Ans 6:

Class : Class 8
positive charge is acqired

Ans 7:

Class : Class 8
Answer is A... positive charge is acquire by the glass rod

Ans 8:

Class : Class 9
When rubbed with fur, glass will become negatively charged. However if silk is used instead of fur, glass will acquire a positive charge.

Ans 9:

Class : Class 6

Post Your Answer

Subject :NSO    Class : Class 8

Ans 1:

Class : Class 10

Ans 2: (Master Answer)

Class : Class 1
The correct answer is C.

Ans 3:

Class : Class 5
Why

Ans 4:

Class : Class 10

Ans 5:

Class : Class 10
Protons don't move.

Post Your Answer

Subject :NSO    Class : Class 5

Ans 1:

Class : Class 8
It should be option C. It should be discouraged.

Ans 2:

Class : Class 5
D

Ans 3:

Class : Class 5
D

Post Your Answer

Subject :NSO    Class : Class 4

Post Your Answer

Subject :NSO    Class : Class 10

Ans 1: (Master Answer)

Class : Class 1
The correct answer is D.

Post Your Answer

Subject :NSO    Class : Class 5

Ans 1:

Class : Class 10
B

Ans 2:

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 3: (Master Answer)

Class : Class 1

Ans 4:

Class : Class 8
D or B not sure.

Ans 5:

Class : Class 7
B is the answer to this question

Ans 6:

Class : Class 9
d

Ans 7:

Class : Class 5
B is the correct answer

Ans 8:

Class : Class 5
C is the correct answer

Ans 9:

Class : Class 6
b

Ans 10:

Class : Class 5
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 11:

Class : Class 4
iron-nickel alloy notable for its lack of expansion or contraction with temperature changes. hence all metals do NOT expand

Ans 12:

Class : Class 9
B is the answer

Ans 13:

Class : Class 3

Ans 14:

Class : Class 5
b as Y expands more

Ans 15:

Class : Class 5
cONFUSED IN d AND B

Ans 16:

Class : Class 3
b

Ans 17:

Class : Class 5
B is the right answer

Ans 18:

Class : Class 5
D or B? please vote

Ans 19:

Class : Class 4
sof does not reply that is why we are confused

Ans 20:

Class : Class 8
The answer should be opt.B

Ans 21:

Class : Class 3
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 22:

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 23:

Class : Class 9
B m kids because Y is only curled much . dont get angry

Ans 24:

Class : Class 9
B because if Y expands and X contracts, X will be a lot smaller than Y. Here, both are almost the same size.

Ans 25:

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

Post Your Answer

Subject :NSO    Class : Class 8

Ans 1:

Class : Class 8
it should be a

Ans 2:

Class : Class 10
the answer is wrong.....it should be a

Ans 3:

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

Ans 4:

Class : Class 9
The correct answer is AAAAAAA

Ans 5:

Class : Class 9
answer A

Ans 6:

Class : Class 8
the answer will be 'A'

Ans 7:

Class : Class 9
Yes the answer is A

Ans 8:

Class : Class 10

Ans 9:

Class : Class 10
What is the correct answer A or C ???????

Ans 10:

Class : Class 8
Yes it is A

Ans 11:

Class : Class 9

Ans 12:

Class : Class 8
A

Ans 13:

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 14:

Class : Class 5
And for this question must be A

Ans 15:

Class : Class 8
Yes it should be A .

Ans 16:

Class : Class 8
cation(Zn2 ) must be deposited to the cathode.

Ans 17:

Class : Class 8
answer is a

Ans 18:

Class : Class 10
my apologies for the previous explanation answer is : C

Ans 19:

Class : Class 9
It has to be A.

Ans 20:

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 21:

Class : Class 7
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 22:

Class : Class 8
WWWWRRRROOOONNNNNNNNNNGGGGGGGGGGGGGGGGG

Ans 23:

Class : Class 10
thus answer is a

Ans 24:

Class : Class 8
Answer is a

Post Your Answer

Subject :NSO    Class : Class 3

Post Your Answer