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[33oomar]

please help in
q5 paper 1 may/june 2006

[Shazizzzle]

Help with O/n 03 q 27 .. ans is  B .. WHY ?
Thanks in advance!

It's a steel ball. When a metal such as iron or steel is brought near a magnet, magnetism is INDUCED in it, i.e haphazard domains arrange, and the metal is always ATTRACTED. Thus, the steel ball, which is unmagnetised, will become magnetised, i.e will be ATTRACTED to the N pole.

[The Golden Girl =D]

I have already given my IGCSEs

r u takin AS or smthn ?

[Vin]

Help with O/n 03 q 27 .. ans is  B .. WHY ?
Thanks in advance!

ok the steel ball rolled is attracted to the magnet so it deflects upwards .. however u may ask why didnt it 'stick' the magnet .. probably because the ball is pushed with a force which overcomes the strength of the magnetic field ..

[Shazizzzle]

ok the steel ball rolled is attracted to the magnet so it deflects upwards .. however u may ask why didnt it 'stick' the magnet .. probably because the ball is pushed with a force which overcomes the strength of the magnetic field ..

Yes, in other words, the force applied in the 'push' is greater than the pull of the magnet, thus it IS ATTRACTED, however continues forward motion, but the attraction creates deviation of path, i.e deflecting in towards the N.

[ambitious94]

As soon as the metal files off the stone it gets cooled .. hence the person doesnt feel anything .. It has a low thermal capacity meaning looses fast  

Thanks VIN, ur a blessing =D

[Vin]

please help in
q5 paper 1 may/june 2006

Answer is B for the simple reason because umm .. lets start from A .. 1 g, 1 g, 5 g, 10 g .. no matter where u place them 5 g, 10 g spoil the broth
B- 1 g, 2 g, 2 g, 5 g .. u can place 1 g, 2 g, 2 g on one side and 5g on the other to balance .. try the others u wont get them ..

[8T]

It's a steel ball. When a metal such as iron or steel is brought near a magnet, magnetism is INDUCED in it, i.e haphazard domains arrange, and the metal is always ATTRACTED. Thus, the steel ball, which is unmagnetised, will become magnetised, i.e will be ATTRACTED to the N pole.

You mentioned that it is attracted to N which means south pole of the ball is attracted..
Main question why not A??
Thanks 4 the effort (:

[Vin]

Thanks VIN, ur a blessing =D

thanks actually a typo .. i meant.. at the end "looses heat faster"

[the_grim_reaper]

nonono! haha, look, the current for the first round will move from positive to negative terminal , next, it will move from negative to positive, this keeps on happening..

hahaha thanks!!!!!!!! U're a life saver. Just 1 final thing, this explains why a capacitor won't charge with AC cause it will prevent accumulation of charges right?? Meaning it will charge and discharge??? And to produce an induced EMF, is it necessary to use an alternating field (the one provided by AC)?? Since DC will not produce an alternating field and no induced EMF right?

[Vin]

You mentioned that it is attracted to N which means south pole of the ball is attracted..
Main question why not A??
Thanks 4 the effort (:

See its a metal ball .. it doesnt hav a pole until another magnet 'sticks' to it .. S or N .. doesnt matter for the ball

[Shazizzzle]

You mentioned that it is attracted to N which means south pole of the ball is attracted..
Main question why not A??
Thanks 4 the effort (:

See, the ball is UNMAGNETISED.
When it is exposed to N of magnet, that side automatically gains the S pole.
Thus, it ATTRACTS to the North.
In A, however, the ball is deflect downwards. That would mean it is repelling, which it is NOT.
Unlike poles attract!

[33oomar]

Answer is B for the simple reason because umm .. lets start from A .. 1 g, 1 g, 5 g, 10 g .. no matter where u place them 5 g, 10 g spoil the broth
B- 1 g, 2 g, 2 g, 5 g .. u can place 1 g, 2 g, 2 g on one side and 5g on the other to balance .. try the others u wont get them ..

Oh i got it now
Thanks a lot Homie

[Vin]

hahaha thanks!!!!!!!! U're a life saver. Just 1 final thing, this explains why a capacitor won't charge with AC cause it will prevent accumulation of charges right?? Meaning it will charge and discharge??? And to produce an induced EMF, is it necessary to use an alternating field (the one provided by AC)?? Since DC will not produce an alternating field and no induced EMF right?

ok u said "a capacitor won't charge with AC cause it will prevent accumulation of charges right??" PERFECT!

 " Meaning it will charge and discharge"  i dont think it will charge on the first place because the to and fro is so fast tht the capacitor wont be able to have enough time to get charged ..

" And to produce an induced EMF, is it necessary to use an alternating field (the one provided by AC)?? Since DC will not produce an alternating field and no induced EMF right?"   yup this is right .. do you know WHY ac is needed for induced pd ??

[8T]

See, the ball is UNMAGNETISED.
When it is exposed to N of magnet, that side automatically gains the S pole.
Thus, it ATTRACTS to the North.
In A, however, the ball is deflect downwards. That would mean it is repelling, which it is NOT.
Unlike poles attract!

oH.. I didnt know it automatically gains S pole .
Many Thanks.