Physics: Post your doubts here!

[omg]

Thank you so much!

Also, for this question, To find the total EMF, why are we subtracting 12 from 20? Shouldn't we be adding to find the total emf? :s

and for part (ii) , why can't I use the formula P=V2/R to find the power of G?

Welcome


erm are you sure you posted the right screen shot?

 

[Studydayandnight]

Welcome


erm are you sure you posted the right screen shot?

Nop, Omg, sorry my bad

It's this one.

 

[sasuke474]

Try to ask your lecturer to let you in for at least 1 lesson. Other than that, there's not much you can do for the practical. Just make sure to read the instructions carefully and don't waste marks unnecessarily on careless mistakes like significant figures. Really watch your significant figures. Good luck!

Any rules you might know of working with sig figs? I mean I know the idea but is there something you're likely to confuse in the exams?

 

[Studydayandnight]

So for this question there's a part (iii), which requires us to:

Calculate the current in the battery.

How do we the get the resistance as 2? :s The correct answer is 6 A.

 

[eliyeap]

Any rules you might know of working with sig figs? I mean I know the idea but is there something you're likely to confuse in the exams?

For the practical, make sure you standardize all of the sig fig for the measurements and calculations that you do. For example, you are plotting a graph of resistance against length. The resistance is from the resistors that you alter. The sig fig for these values don't matter because you aren't measuring it. However the length you are measuring, hence the sig fig matter. Then the values for gradient and etc must also have the same sig fig as the length.
If you calculate 2 values each with a different sig fig ( lets say 1 sig fig and 2 sig fig), the resultant value, the sig fig you take the lower one which is 1 sig fig. Good luck!

 

[Sahil Gupta]

could someone draw the vector diagram for 02/M/J/07 question number 4d) please!

 

[Sahil Gupta]

explain this please

 

[funky brat]

How do we do this? :'(

What's the answer? You can use dsintheta= n*wavelength where d=1/n.

 

[funky brat]

explain this please

See you have the horizontal component of velocity which is equal to ucostheta.Here it is given as 8.2. Using this and the angle cos60 evaluate u which is 16.5. Then for vertical component use formula usintheta using 60 as theta and 16.5 as u, you will get 14.2.

 

[funky brat]

So for this question there's a part (iii), which requires us to:

Calculate the current in the battery.

How do we the get the resistance as 2? :s The correct answer is 6 A.

emf is 12 and internal resistance is 0.5 which gives the current as 6 A. For resistance R=V/I where voltage is 12 and current is 6.

 

[Suchal Riaz]

Asif1223 =
I ∝ A²
for I to double, A² must double
so for A² to become double, A must be multiplied by √2
as
I2 = (√(2)A)²
I2 = 2A² but I = A² so
I2 = 2(I)

got it?
this is the thread to ask questions, that thread was not for questions. Please delete your post. here is the link to your post: https://www.xtremepapers.com/commun...ck-last-day-revision.32432/page-6#post-916940

 

[Studydayandnight]

emf is 12 and internal resistance is 0.5 which gives the current as 6 A. For resistance R=V/I where voltage is 12 and current is 6.

It gives 24 not 6. :/

Emf is 12, internal resistance is 0.5 so I=V/R which is 12/0.5 which is 24.

 

[Studydayandnight]

How do we do the 2nd question? :'(

answer is 4.93 ms^-2

Answer for the magnitude is 6.9 x 10^-5

HELPPPPPPPPPP

 

[amal sharkawi]

can anyone plz answer ???

 

[qdkhan]

can anyone please explain q3 b(III) in the following paper?
http://revision.peterhouse.co.zw/Ph... & Mark Schemes June & Nov/9702_s12_qp_21.pdf

 

[TheJDOG]

View attachment 53547
can anyone explain this plz???

There is a way to change from decimal to binary and binary to decimal,
Here you go changing binary to decimal is a but more confusing, tell me ill try to explain more , are my answers correct though?

 

[Fate0]

Hello.
I was wondering if any of you could help or share some resource with me regarding Kirchhoff's Second (Voltage) Law.
I just cant seem to make sense of the sign conventions used. Is there any easier way of assigning signs. Any help is appreciated.

 

[tiki-taka]

any idea on calculating area under graph quickly without counting boxes for ages..
TheJDOG
Suchal Riaz
funky brat

 

[afrolina]

no. of significant figures for cie as level?

 

[qwertypoiu]

View attachment 53547
can anyone explain this plz???

Hi is this in A2 or AS???