How was 9702_12_W15??

[xwave23]

For the extension question you had to calculate extensions of both the materials seperately and add them.
By the formula Young's modulus= FL/AE.

 

[Muzammil Khan]

For the extension question you had to calculate extensions of both the materials seperately and add them.
By the formula Young's modulus= FL/AE.

You know it was yesterday when i came across this formulae in which if 2 wires are connected in series young modulus is (2y1y2)÷(y1+y2), this made this question a lot easier.

 

[Muzammil Khan]

What was the ans of that ultimate tensile stress of ductile material?

 

[xwave23]

I dont really remember bro.
I just hope i didnt get it wrong. XD

 

[Harsheys]

Yah I checked, that was a past paper question and it WAS nucleons at 400 s-1 luckily. Question was pretty vague, what do you mean material? xD

Supposedly it's the water waves tho, think water waves is the answer because it's the only transverse wave in the question.. Others were stationary.. at the time I said the thunderclap sound because I imagined diffraction occurring in B instead of polarisation, but that clearly was unreasonable reasoning xD

Actually it's supposed to be the stationary wave on a wire.
Water waves cannot oscillate on more than 1 plane, and stationary waves can also be polarized, google it

 

[ahmedish]

I answered C.. not quite sure why but if I draw free body diagrams, I think it's C..
The brass steel I answered B I guess.. 4.0 x 10 to the power of -4 or something like that, I kind of forgot bout that one haha xD

so the force exerted is less than F ?? I did that as well because theyre accelerating im not sure if im correct but it might be

 

[Albert Lianto]

so the force exerted is less than F ?? I did that as well because theyre accelerating im not sure if im correct but it might be

I think B is incorrect because if B is the answer, then if you take the lighter block separately, it would accelerate faster than it should, which is why I said C..

 

[Harsheys]

so the force exerted is less than F ?? I did that as well because theyre accelerating im not sure if im correct but it might be

I said the force exerted on Y is the same as F, I don't get how they would exert different forces on each other.

 

[Albert Lianto]

Hey guys, at which instance is no work done?
A the air in the tyre is moves out of a tyre after a puncture
B (something) falls
C box moves at a constant horizontal speed along a frictionless surface
D (forgot the other one haha)

I answered C.. not exactly sure.. what did you guys answer?

 

[ahmedish]

I said the force exerted on Y is the same as F, I don't get how they would exert different forces on each other.

I think B is incorrect because if B is the answer, then if you take the lighter block separately, it would accelerate faster than it should, which is why I said C..

they both have the same acceleration a, and they have different masses so mass X multiplied by a will give a higher value for the force F than that exerted on Y. I think im correct

Hey guys, at which instance is no work done?
A the air in the tyre is moves out of a tyre after a puncture
B (something) falls
C box moves at a constant horizontal speed along a frictionless surface
D (forgot the other one haha)

I answered C.. not exactly sure.. what did you guys answer?

C 100%

 

[Shujaat Khan]

Time factor was a problem. I couldn't analyse all questions in given time and had to rush like 3 questions(guessing without thinking)

What was the Fork one end open pipe whcih gives length 25 answer?
I put 75 and 125 over there( I didn't know the answer I'm sure it should have been somewhere with proportion of lamhda)

 

[Shujaat Khan]

What was the answer to that one, in which a car was going down the slope???

I forgot the answer but I did apply the mechanics formula
GPE(initial)+ KE(ini)= GPE(final)+KE(final) + Work done by friction.
answer obtained easily using this

 

[The Sarcastic Retard]

I forgot the answer but I did apply the mechanics formula
GPE(initial)+ KE(ini)= GPE(final)+KE(final) + Work done by friction.
answer obtained easily using this

I did : workdone = F * d
G= mass * 9.81
I found the d by v^2 - u^2 = 2as
Got d.
I got A.
Why this is wrong?

 

[ahmedish]

I did : workdone = F * d
G= mass * 9.81
I found the d by v^2 - u^2 = 2as
Got d.
I got A.
Why this is wrong?

u have 2 unknowns, the work done by friction and the force of friction....
what did u multiply d with?
its supposed to be 500x9.81x30 - 0.5x500x11^2 i think or the opp

 

[Albert Lianto]

I forgot the answer but I did apply the mechanics formula
GPE(initial)+ KE(ini)= GPE(final)+KE(final) + Work done by friction.
answer obtained easily using this

Are KE(ini) and GPE(final) both zero in this instance? What answer did you get?

u have 2 unknowns, the work done by friction and the force of friction....
what did u multiply d with?
its supposed to be 500x9.81x30 - 0.5x500x11^2 i think or the opp

What letter was the answer?

Time factor was a problem. I couldn't analyse all questions in given time and had to rush like 3 questions(guessing without thinking)

What was the Fork one end open pipe whcih gives length 25 answer?
I put 75 and 125 over there( I didn't know the answer I'm sure it should have been somewhere with proportion of lamhda)

Pretty sure 75 and 125 (D) was the answer.. 75 and 125 gives nodes in the closed end..

 

[Shujaat Khan]

Are KE(ini) and GPE(final) both zero in this instance? What answer did you get?

Don't remember the answer. And yeah ke ini and gpe final are both zero
I was just giving the formula to anyone who had doubt about their method so they can confirm whether it was good or not

I did : workdone = F * d
G= mass * 9.81
I found the d by v^2 - u^2 = 2as
Got d.
I got A.
Why this is wrong?

Someone said it was wrong? I mean I don't remember the answer but pretty sure you can do it by 2 methods
If my maths teacher saw this he would probably be so angry lol you can do this faster by energy, why complicate life by going through long methods.
And yeah what did you take F as? You got only d by what I see.
F stand for the friction in your formula right?
Did you use mgsin @? but then @ is unknown in the question.
Oh I see you used the height and value of d to get sin @ right?
Well you will get the answer this way but it's waste of time when you could have just gone energy

 

[Huzaifa_12345]

Easiest P1 paper I've done - GT is minimum 30.

 

[The Sarcastic Retard]

What was internal resitance ?

 

[The Sarcastic Retard]

I forgot that one, what did you get ? Is it 0.(soemthing) ? What's the answer for that diffraction grating one?

there were no options like in point.
i forgot that question
If m not wrong I chose, R V R V

 

[The Sarcastic Retard]

Don't remember the answer. And yeah ke ini and gpe final are both zero
I was just giving the formula to anyone who had doubt about their method so they can confirm whether it was good or not


Someone said it was wrong? I mean I don't remember the answer but pretty sure you can do it by 2 methods
If my maths teacher saw this he would probably be so angry lol you can do this faster by energy, why complicate life by going through long methods.
And yeah what did you take F as? You got only d by what I see.
F stand for the friction in your formula right?
Did you use mgsin @? but then @ is unknown in the question.
Oh I see you used the height and value of d to get sin @ right?
Well you will get the answer this way but it's waste of time when you could have just gone energy

I got wrong answer though..
I got option A.
I am so confused, I alwaysed use this methid and got corrrect answer I D K where did I made mistake :'(