Physics: Post your doubts here!

[Asad Moosvi]

It reaches terminal velocity after falling about 10m
so we can find how long it takes to fall 10m from the equation s=ut+0.5gt^2
s=10m
ut=0 since initial velocity is zero
g=9.81
therefore t is about 1.43 s
so it reaches terminal velocity(7ms^-1) at about 1.43 s

But in the answer it says it has to be between 1.5s and 3.5s.

 

[Asad Moosvi]

the terminal velocity is given in part c(ii) 1 n the distance is also given so we will simply find the time by any kinematics equation...

All I see is a bunch of weird symbols.

 

[Snowysangel]

IS the decay constant in the AS level syllabus ?

 

[omaaaar]

Thought blocker
Could you tell me all the formulas to be used in waves

 

[DeViL gURl B)]

DeViL gURl B) help please

As u move along .. U know u see bright and dark fringes that is exactly what implies Here as well.. The dark fringes go for the minima and light go for the maxima .., in the same manner if u gi with the dots indicated .. U can say that If at O it is bright.. Then go along the dots and as u reach P is is maxima that is bright!
And u can say the readings go from maxima to minima ...and vice verse.
Hope it helps ya

 

[forever_chocoholic]

IS the decay constant in the AS level syllabus ?

no it is not included

 

[Zepudee]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s13_qp_23.pdf

Q1(b)(iii) anyone, please? PRETTY PLEASEEEE

 

[forever_chocoholic]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w13_ms_23.pdf
can anyone help me with question 5 c? pleaseeeeeeeeeeee

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w02_qp_2.pdf
AND can someone explain how to solve question 5 (b) please !!!!

 

[mehria]

All I see is a bunch of weird symbols.

which symbols?

 

[Snowysangel]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s13_qp_23.pdf

Q1(b)(iii) anyone, please? PRETTY PLEASEEEE

As you can see from the equation, F and I are directly proportional so it has to be a straight line passing through the krigin

 

[danial 234]

As you can see from the equation, F and I are directly proportional so it has to be a straight line passing through the krigin

nop.. it will be a curve with increasing gradient because f is proportional to I^2

 

[_Ahmad]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_w10_qp_22.pdf

Can anyone PLEASE explain Q4 b i) and ii)

 

[trao11]

Hey,
So question 4 (b) (i) is the area between the two lines, because that is the energy lost
For 4 (b) (ii), you need to find the area between the two lines, by counting squares.
Hope that helps.

All the best.

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_qp_22.pdf

Can anyone PLEASE explain Q4 b i) and ii)

 

[TheJDOG]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w13_ms_23.pdf
can anyone help me with question 5 c? pleaseeeeeeeeeeee

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w02_qp_2.pdf
AND can someone explain how to solve question 5 (b) please !!!!

Hello for the ripple tank question 5 c,

They asked us to draw and explain, you need to draw the ripple tank and label, you need to show a light source and label it, and draw a screen and also you need to tell them that you use a video camera to observe the waves.



For 5b, if you look at the wave T1, you'll see that 1 Wavelength is 6 blocks.
We know that 1 Wavelength is 360 degrees.
It's given that T2 lags 60 degrees behind.
So we do, 360---> 6 blocks
60-----> ? Blocks

So this means that t2 lags behind t1 by one block.
When you draw t2 it has to have the same Amplitude A as of T1
Superposition principal : When two waves meet, total displacement is the vector sum of the individual displacements of the waves.

If I have any mistakes someone correct me Good luck on tomorrow's Physics P2 guys

 

[umair1161]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s13_qp_22.pdf

Q5 (b) Please!

Thanks in advance!

 

[trao11]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s13_qp_22.pdf

Q5 (b) Please!

Thanks in advance!

The nodes are the points with 0 displacement, and antinodes are regions with maximum amplitude
For part (ii) you need to see how many wavelengths appear in the length PQ. For PQ, you have 1.5 lamda, and the frequency is 0.80. Hence the distance is 0.80*1.5 = 1.2

I didn't understand part (iii), can someone please help with that? Thank you

I hope that answers your question adequately
All the best for tomorrow.

 

[marimin]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s11_qp_22.pdf question 2b (2) how to draw the graph?? please help and explain....

 

[umair1161]

The wave produced reflects of point Q on the wall. The incident and reflected waves have the same speed and frequency, and interfere at various points across the string. This produces a stationary wave.

I hope that answers your question adequately
All the best for tomorrow.

Im sorry but can you please elaborate please! Please write out a full answer as you would write in the exam!

Thank You

 

[trao11]

Smaller radius means smaller force, and hence smaller acceleration.
It will be of the same shape, below the original curve

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_22.pdf question 2b (2) how to draw the graph?? please help and explain....

 

[TheJDOG]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s13_qp_22.pdf

Q5 (b) Please!

Thanks in advance!

Hello, for Q5 b I,
Anti nodes are the points where there is maximum displacement of the wave, in this case, they're three antinodes.
Nodes are the points where there is zero displacement, in this case, they're 4 nodes, including 2 nodes at P and Q.
For Ii) look at Wave PQ carefully, you'll see that it's 1.5 lambda.
In part a) you already worked out lambda and got that it's 0.8m
So for length of PQ just substitute and you'll get Length= 1.5 x 0.8 = 1.2 m

For part three, look 2 pages back in this thread and you'll see the explanation with an animation.