Physics: Post your doubts here!

[shahzaib ihsan]

guys look at question 11 on this paper:
http://www.teachifyme.com/wp-content/uploads/2016/08/9702_s16_qp_11.pdf

how is the 2nd column correct? (mv sin30=MV sin40)

 

[Holmes]

View attachment 62544

 

[Holmes]

 

[shahzaib ihsan]

View attachment 62546

View attachment 62547

the answer is c?

 

[Holmes]

the answer is c?

yes

 

[MarcosT200]

we first need to find the voltage in the external resistance. so using v=ir
hence v=5.5v. since the all of the components are parallel to each other they all have an terminal potential difference of 5.5v
current going into the junction= output of junction.
so the current going into the internal resistance is 0.25A. 0.5/2 as both components have the same p.d and internal resistance they both have the same current
simply then use the formual
terminal p.d=Emf-Ir
5.5=6-0.25r
hence r is 2 ohms

I have a question:

Since the terminal pd's of the battery's in parallel are equal, isn't there supposed to be NO current flowing through the batteries? And therefore the 0.5 A only come from one of the batteries?

Thank you,

 

[husnain99]

Why the ans is C ?

 

[GarryTheGhost]

any angels still awake???

 

[Aishayasin]

Answer is D

 

[Your 69Mom]

Can someone explain why the answer is C? URGENT!

 

[Metallic9896]

How did it go guys? Mine was pretty good. It was a nice interesting paper, a bit weird perhaps. I noticed this year in P2 and P1 they seemed to focus more on units and definitions such that they even included derivation in p1 o_o Overall it was nice. Expecting 35 and above. For sure got 2 wrong after discussing with friends, rest of which that I discussed were correct. Dunno about the remaining.

 

[anastasia grey113]

How did it go guys? Mine was pretty good. It was a nice interesting paper, a bit weird perhaps. I noticed this year in P2 and P1 they seemed to focus more on units and definitions such that they even included derivation in p1 o_o Overall it was nice. Expecting 35 and above. For sure got 2 wrong after discussing with friends, rest of which that I discussed were correct. Dunno about the remaining.

well i found it difficult
i already know i lost 5 marks
idk how high the gt will be for this one :/

 

[Metallic9896]

well i found it difficult
i already know i lost 5 marks
idk how high the gt will be for this one :/

Oh darn. Many others ik found it to be difficult and awkward too. Shouldnt be more than 30 for an A. And overall physics is lower than others like chem and bio so dont worry if your other phy papers went well.

 

[Zaki ali asghar]

I found it alright,neither difficult nor easy.There were many repeated qs fortunately so time management wasnt an issue

 

[Zaki ali asghar]

My guess is that gt gonna be 27-28

 

[Zaki ali asghar]

It can be lower than that as well but cant be higher than that!!

 

[Shimmery woods]

How did it go guys? Mine was pretty good. It was a nice interesting paper, a bit weird perhaps. I noticed this year in P2 and P1 they seemed to focus more on units and definitions such that they even included derivation in p1 o_o Overall it was nice. Expecting 35 and above. For sure got 2 wrong after discussing with friends, rest of which that I discussed were correct. Dunno about the remaining.

i found it difficult :/

 

[amina1300]

How did it go guys? Mine was pretty good. It was a nice interesting paper, a bit weird perhaps. I noticed this year in P2 and P1 they seemed to focus more on units and definitions such that they even included derivation in p1 o_o Overall it was nice. Expecting 35 and above. For sure got 2 wrong after discussing with friends, rest of which that I discussed were correct. Dunno about the remaining.

I was EASY !! But I'm so dumb I got the first Q wrong because I just didnt think!! 15 ms-1 !!

 

[amina1300]

Discuss your questions....

 

[Zaki ali asghar]

Was the ans to firs q 12 or 9?