Pure Physics MCQ Aftermath
-
Originally posted by eagle:
I can't see the graphic in office.
Can upload to say... your yahoo geocities account if you have one?
I don't have... so you can't see the picture hosted by imageshack, photobucket, tinypic and other public image hosting websites?
-
oh oops my fault pai seh. Electromagnet.
-
Originally posted by [e].Le-V:
I don't have... so you can't see the picture hosted by imageshack, photobucket, tinypic and other public image hosting websites?
no
-
yup, solenoid , it's less complicated that way.
if it is magnet, i think have to think long long
-
Inside solenoid should have strongest magnetic field I believe
Outside solenoid, the wire effects could cancel each other out... Hard to draw out here to explain why...
-
so the answer is B la, woot!
-
the right hand grip rule loh.
==================> A
C
<================== B
D
the field at D because of A is into paper,
the field at D because of B is out of paper,cancel out.
the field at C because of A is into paper,
the field at C because of B is into paper,reinforce
-
NO!!!! -2 marks :(:(
-
I also -2 marks. Knn I want to jump into Singapore River liao la. So wasted.
-
where did you minus 2?
-
The waves question about whether Q will move up or remain stationary. I put stationary because it is stated in my FYS. See I tio scammed until don't know.
The second one is the circuit question, to achieve 6 ohms, that is an over-looking on my part.
See so stupid right. Can go bang wall die la.
-
Originally posted by Garrick_3658:
The waves question about whether Q will move up or remain stationary. I put stationary because it is stated in my FYS. See I tio scammed until don't know.
The second one is the circuit question, to achieve 6 ohms, that is an over-looking on my part.
See so stupid right. Can go bang wall die la.
ohyeah for the first one my classmate also said its in fys.
second one was kinda like a trick qn for those that are not careful
-
Originally posted by davidche:
ohyeah for the first one my classmate also said its in fys.
second one was kinda like a trick qn for those that are not careful
*points finger at me*
Don't have those. I think I am the only one who made this mistake. EVER.
second one was kinda like a trick qn for garrick who is not careful
Done.
-
Originally posted by Garrick_3658:
*points finger at me*
Don't have those. I think I am the only one who made this mistake. EVER.
Done.
not tat bad lar. Maybe only you did the fys qn.
-
Originally posted by eagle:
Inside solenoid should have strongest magnetic field I believe
Outside solenoid, the wire effects could cancel each other out... Hard to draw out here to explain why...
there's a soft iron core too
it should only strengthen the magnetic field right?
if not then i 36 liao T.T
-
Hello peops. I have some opinions on qn 37..
My answer is B.
Based on research in wikipedia, http://en.wikipedia.org/wiki/Electromagnets, under the title Magnetic circuit, they say, " Most of the magnetic field will be concentrated in the core." As the strength of the field is determined by the number of field lines present, at point Y ( the centre of the solenoid), there should be strongest magnetic field strength when compared to the points outside X and Z.
I think some people would choose A because they thought magnetic effect on magnetic materials outside the core and magnetic field strength is the same. It is right and logical when people thought that the poles are the strongest because it attracts the most magnetic materials ie iron filings, when compared to the core ability to attract iron filings. I think the most probable explanation for this is that the magnetic field lines within the core is not "outside" when compared to the magnetic field lines at the ends- where the magnetic field lines loop back from North pole to South pole. As a result, the magnetic effect on magnetic materials ,such as iron filings, is the strongest at the poles and not at the core.\
In conclusion, the magnetic field strength should be the strongest within the core and not at the ends. On the other hand, the magnetic effect on magnetic materials such as iron filings is the strongest at the ends and not at the core physically.
Anyone thinks that it is improbable just comment. Thanks.