physics mcq help needed! urgent!

[ifraha18]

yea..

[ifraha18]

q14 ,30,34 and 16 june 2008..?

[neno]

Q16 june 2008:
workdone=energy and workdone=force times the distance in the same direction at the force applied so since the force is acting in the same direction as the distance s so the enegy is equal to fs...and when the charge moves 4rm x to y then the distance from the sorce increases and more the distace increases the less the force is thts y it decreases

[ifraha18]

thnku.

[neno]

Q14 thr are 2 things ahppining here a couple and a moment so the couple shud be equal to the change in moment
notice tht the forces F are acting on the same place so thts the couple
while Wx2a-Wxa shud be equal to the couple
Wx2a-Wxa=Fxh(in couple u jst take 1 force X the distane between them)
therefore W2a=Fh+Wa

[ifraha18]

oryt.Thanks.

[neno]

u noe the rule cos theta =adjacent over the hypoteneous
so in this case cos theta X v shud be equal to the adjacent which it u
so cos theta x v=u
v=u/cos theta

[ifraha18]

thkss

[ifraha18]

q34 jne 2008.?

[neno]

ur welcome can u help me with some questions
oct/nov 2007 Q37,Q32,Q25

[neno]

Q34 they said tht the volume of the wire is constant
so the volume of a cylinder is its lengthXthe crosssectional area
so for x imagine the area is 1 and the length is 1 so the volume is 1
but for y the length is 4 but it still has the same volume so therefor 4Lxa quater area will give the same volume which is 1
and resistance in a wire is equal to length over area
so in this case 4/0.25 which is equal to 16

[ifraha18]

q 4,32 of nov 2008?>>>

[superduper2009]

can sum1 explain 1 20, 25 of october november 07 paper 1
 (cie)
thanks alot

[ifraha18]

oct nv 2007 32. as the lyt increases resistance acros ldr decreases n do does the voltmeter reading. so its A

[neno]

oct nv 2007 32. as the lyt increases resistance acros ldr decreases n do does the voltmeter reading. so its A

but isnt it tht the resistance in a ldr depends on the lightintensity the more the light the more the intensity??