Physics: Post your doubts here!

[Light Yagami]

Why is the answer C:-

 

[Hassan Ali Abid]

suppose the wavelenght of this is 2cm.....when 2 loops are produced the wavelenght decreases to 1cm .......when wavelenght decreases Frequency increases so it becomes to 2F ...
* not sure about the explaination but i think so we have to do this in this way

 

[Ahmedraza73]

Why is the answer C:-
View attachment 22234

use first harmonic and second harmonic for a fixed length of string:
lamda =2 so frequency will be f
lamda =1 frequency will be 2f

 

[Nagaanusan]

Hi everyone, AsSalamoAlaikum Wr Wb...

To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!

So post your PHYSICS doubts in this thread. InshaAllah other people here will help me and you all.

NOTE: If any doubts in the pastpapers, please post the link! You can find links here!

Any Physics related notes and links will be added here in this post. Feel free to provide the links to your notes around the forum, or any other websites!
Thanks!
Jazak Allah Khair!

Physics Notes:

Some links & Notes - by destined007

Physics Practical Tips - by arlery

Notes for A2 Direct Sensing (Applications) - shared by sweetiepie

Physics Summarised Notes (Click to download)

AS and A-Level Physics Definitions

A2: Physics Revision notes - by smzimran

Paper:5 Finding uncerainty in log - by XPFMember

Physics Paper 5 tips - by arlery

Physics Compiled Pastpapers: <Credits to CaptainDanger for sharing this..>

Here are the compiled A level topical Physics questions in PDF form...

Paper 1 : http://www.mediafire.com/?tocg6ha6ihkwd

Paper 2 & Paper 4 : http://www.mediafire.com/?g65j51stacmy33c

(Source : http://www.alevelforum.com/viewtopic.php?f=15&t=14)

can u pls answer this question
An insect of mass 4.5mg flying with a speed of 0.12m/s-1,encounters a spider's web which brings it to rest in 2.0ms .calculate the average force exerted by the insect on the web.

this is an phy AS level question under momentum topic​

 

[Tkp]

Why is the answer C:-
View attachment 22234

the first 1 is fundamental.so the wavelength is 2l and f for the fundamental.Fr the second harmonic motion the wavelngth is l and the frequency is 2 l.

 

[Tkp]

Why is the answer D:-
View attachment 22229

f=kx(take extension in m)
so 12/(100/1000).so the ans is c.

 

[snowbrood]

can u pls answer this question​

An insect of mass 4.5mg flying with a speed of 0.12m/s-1,encounters a spider's web which brings it to rest in 2.0ms .calculate the average force exerted by the insect on the web.​

​

this is an phy AS level question under momentum topic​

favg is the average force
Favg * t = change in momentum

Favg * 2 * 10^-3 = mv - mu (v is final velocity u is initial velocity)

Favg * 2 * 10^-3 = 0 - 4.5*10^-3 * .12
now calculate for average force

 

[shinnyyy]

f=kx(take extension in m)
so 12/(100/1000).so the ans is c.

ans is C

 

[usman]

A facebook group for Further Maths, intended to remove your doubts and solve your problems. Check it out:- http://www.facebook.com/groups/furthermathsprodigies/

 

[Nagaanusan]

favg is the average force
Favg * t = change in momentum

Favg * 2 * 10^-3 = mv - mu (v is final velocity u is initial velocity)

Favg * 2 * 10^-3 = 0 - 4.5*10^-3 * .12
now calculate for average force

u r awe great

 

[Hassan Ali Abid]

ans is C

f=kx(take extension in m)
so 12/(100/1000).so the ans is c.

the answer of this is D not C

 

[1357913579]

the answer of this is D not C

f=kx
where 'x' is the change in length
k=f/x ; 12/(100-40)/1000 = 200Nm^-1

 

[Scafalon40]

Guys can someone help me with this?

If you have a raw data value like l= 6.0 +/- o.4 and you're asked to calculate l^2 and write down its absolute uncertainty, how do you know what the no of significant figures for the uncertainty should be?
And what about a number like x=750 +/- 20 and you're asked to do the same thing as above, only this time it's ln(x) which you have to calculate.
All I need to know is how many s.f should the uncertainty be quoted to.
Thanks!

 

[Muhammad TAimoor]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_w05_ms_1.pdf
Mcq no. 21.
How do we solve it?!

 

[Ahmedraza73]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w05_ms_1.pdf
Mcq no. 21.
How do we solve it?!

the link that u have provide is fr marking scheme
Where is the Question Man?

 

[Tkp]

f=kx
where 'x' is the change in length
k=f/x ; 12/(100-40)/1000 = 200Nm^-1

damn.didnt see that it was 40 at first.the ans is d

 

[snowbrood]

u r awe great

hehe thanks buddy

 

[snowbrood]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w05_ms_1.pdf
Mcq no. 21.
How do we solve it?!

well frequency is going to be same in both cases as frequency depends on the source now just plug in values in the equation v=fw(let w equal to wavelength)
1500=150w1
w1=10
then
300=150w2
w2=2
hope u get it

 

[sandwich147]

Hi, I'm new here. anyone have a good A2 notes on oscillation? I'm having a hard time studying the topic. Thanks in advanced!

 

[Tkp]

can u pls answer this question​

An insect of mass 4.5mg flying with a speed of 0.12m/s-1,encounters a spider's web which brings it to rest in 2.0ms .calculate the average force exerted by the insect on the web.​

​

this is an phy AS level question under momentum topic​

well u have to know the formula.f=(dell p)/dell t
f=mv/t.(just take the mg in kg and ms in s and u will get the ans)