Physics PAPER 12 discussion :D

[1992]

hey everyone. how did it go the exam???
did anyone put for the one of wavelenght, infrared?? which was 10^-5
also wat was the answer for the steel ball falling, was it a curve??
and the one of current in ammeter?? which diagram was it?? D maibe

 

[intel1993]

yes it was infrared.........
n for the steel ball graph it was B..........
n for that ammeter the ans was c..........

 

[1992]

c for the ammeter, how do u calculate it??
which graph was for steel ball?? like a curve slowing down?? like when it decelerates??

 

[1992]

did anyone remember the one of ice and water?? which one is denser??

 

[zwitterion]

i wrote microwave.
And ammeter one B.
Ice is less dense than water. that is why it floats.

 

[rafae.shaikh]

and what abt the molecular separation? did it increase?

 

[intel1993]

NO,IT DECREASES, THEREFORE,MASS PER UNIT VOLUME or DENSITY INCREASES........

 

[WellWIshER]

NO,IT DECREASES, THEREFORE,MASS PER UNIT VOLUME or DENSITY INCREASES........

absolutely!!!!

 

[1992]

and the one of the slope efecieny ?? what u put?
i put A because it had fv

 

[zwitterion]

I did D for that.
what was the work done from P to Q? was it zero?
And the minimum resultant force 3,4,5N? zero by any chance?

 

[henglin]

and the one of the slope efecieny ?? what u put?
i put A because it had fv

no,
its mgh/fs

 

[zwitterion]

that was option D. =)

 

[1992]

o shit. so i have it wrong :S
were there any more confusing questiuons¿?

 

[zwitterion]

the ammeter 2ohm one was pretty confusing. my mind went blank while doing it. Is the ans B by any chance?

 

[henglin]

the ammeter 2ohm one was pretty confusing. my mind went blank while doing it. Is the ans B by any chance?

its D
when in parallel with other two resistors,
derived from kirchoffs 1st law, the current will be shared....

 

[henglin]

add me as friend i can help ...

 

[1992]

i put D. by calculating it

 

[zwitterion]

Crap. got that wrong then.
tell me about the work done from P to Q one?

 

[henglin]

that question is retarded

0 makes the most sense...
but i chose C i think, how? its 90 degree so its 1/4 of the perimeter, E is proportional to Force, so workdone is FxD, so E x 3.14*r/2

 

[zwitterion]

oh well i did not have the time to work it out so i used the assumption work done in a circle is zero due to the force being cos90.

Were the last 3 options C?