help with 9702_w09_qp22

[XPFMember]

Assalamoalaikum!!

need help with Q:1 c (ii)
why do we quote the fig. to 2 s.f??

 

[Tweety-Angie]

I didn't get your question. Got no paper of 9702_w09_qp22

 

[XPFMember]

http://www.xtremepapers.net/CIE/International A And AS Level/9702 - Physics/9702_w09_qp_22.pdf

 

[Tweety-Angie]

I think it is because the time is in 2 s.f. I'm not sure of it as well. What do you think?? Haven't you referred to mark scheme?

 

[XPFMember]

i didnt understand y it was taken as 9.8 but looks u r right...but in the same paper Q:2 b (i) when data is to 2 s.f then y the final ans is to 3 s f

 

[Tweety-Angie]

It may be because percentage is asked. I don't know the reason sorry! If you get this answer, do post it here

 

[XPFMember]

sure

 

[DragonCub]

There is a regulation for the experiment results which is that the number of s.f. of calculated results must be equal to the SMALLEST No. of s.f. among the measured values. In other words, the accuracy of the calculated value must be the same as that of the most inaccurate value measured.
Here in the question, the smallest No. of s.f. is 2: for Length is 92, 2 s.f.
So g, the calculated quantity, should also be rounded to 2 s.f.

 

[XPFMember]

thanks

need help again with Q: 5 c (ii)
i dont understand it

 

[Tweety-Angie]

thanks

need help again with Q: 5 c (ii)
i dont understand it

There is no question of that number in that year.

 

[XPFMember]

check again plz...there is!!

 

[hassam]

the question is saying that how a STATIONARY wave has a speed....in anser you shud refer to its formation i.e when incident and reflected waves superpose a stationary wave is formed and the speed calculated in part is of these incident and reflected waves that have been superposed

 

[XPFMember]

is my answer correct=> Stationary wave is the result of interference betwween two progressive waves of equal frequency and amplitude travelling along the same line but in opposite directions.They have the same speed!

 

[hassam]

just add these words.....the speed i have calculated in previous part is of these two waves which interfered

 

[XPFMember]

ok Jazak Allah