Paper 3 physics !! get help here :)

[ygyh45]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_w10_qp_33.pdf can u explain question 8 plz

 

[Osmix1995]

hey this question about moments in o/n 2011 question 3 ,, i was able to understand and solve it except fot part B (ii)

 

[ygyh45]

hey this question about moments in o/n 2011 question 3 ,, i was able to understand and solve it except fot part B (ii)

which varient?

 

[Osmix1995]

variant 1

 

[ygyh45]

here P is the pivot and the anitclocwise and clocwise forces are the ones above P and below it so above P is = Fx2 and below P is = (120 x 33) + ( 20 x 15)
then u find F by dividing like usual
hope it helped..

 

[Osmix1995]

yh i know that part but the part under it B(ii)

 

[ygyh45]

i think because of the the weight he is holding tht is causing a force on P and to know forces acting on P u add clockwise and anti clock wise but here u need only the downwards one so u subtract ur upwards one which is F from the total forces acting down ... thats wat i see i dont kno if it has some other explanation hope it helps anyway

 

[Osmix1995]

yh in the mark scheme they did 2130 force at F , and minus 140 ..............could the 140 be the two forces 120 and 20 ?

 

[ygyh45]

yes

 

[Osmix1995]

AHA thank you sis <3 you saved me

 

[ygyh45]

no problem .... can u help solve my question up there?

 

[Osmix1995]

yes , ok here we go

situation a) they are both moving at the same speed the arows indicate same directions so nothing happens because no line magnetic field lines have been cut

situation b) magnetic field lines are being cut so the mV will show reading (small one cuz small magnet)

situation c) should be the same i dont know why there are 2 marks

(i dont know if i am right try and check the MS )

 

[ygyh45]

oh ok thank u soo much

 

[ygyh45]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_w10_ms_33.pdf

 

[sunnyclone]

some1 help me in light refraction n prisms n total internal reflection

 

[Raven Snow]

Guys...I need help in radio activity and half life!!!!...can some one explain me in simple words!!!...and yes I also have a major problem with Fleming's left hand rule....I never got the right answers!!!

K well the half life is the time it takes for half of the radioactive source to decay. So if it's a graph u see u divide the original value by 2 then see how long it takes to get to that value. I'm new at this so sorry if this isn't that helpful.

 

[gasserghoneim]

what happens to speed when acceleration decreases?

 

[ygyh45]

what happens to speed when acceleration decreases?

decreases too...

 

[gasserghoneim]

thnx

 

[Osmix1995]

is there a special rule for velocity?