Physics: Post your doubts here!

[Suchal Riaz]

How do u know Its a right angle trianle :/??

Q4 (B) says "the beam is incident normally..." Which means screen makes 90 degree with beam

 

[Thought blocker]

Q4 (B) says "the beam is incident normally..." Which means screen makes 90 degree with beam

But the diagram itself shows, P is at 90 degree.

 

[kitkat <3 :P]

I guess I am correct. Suchal Riaz

Q4 (B) says "the beam is incident normally..." Which means screen makes 90 degree with beam

Ohhh Got It ^_^ thanks

 

[Faaiz Haque]

Thanks Riaz, i'll view those in a sec.

Also need help with this
http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s11_qp_21.pdf
Question 7 C i and ii
Mark scheme just says correct lines labelled, lol.

 

[Suchal Riaz]

But the diagram itself shows, P is at 90 degree.

It could be 90.2 degree. Dont consider everything perpendicular unless it says so.

 

[kitkat <3 :P]

View attachment 40338

Can u please explain this formula like I dont understand whwt do d and n stand for

 

[hope4thebest]

Can anyone here explain the logic of this question? Ans is 9 V. Thanks in advance

 

[princeali97]

Can u please explain this formula like I dont understand whwt do d and n stand for

d is the distance between each slit and n is the order number

 

[kitkat <3 :P]

d is the distance between each slit and n is the order number

And there was "a" In some formula I forgot it :/ wht does tht mean :/

 

[princeali97]

And there was "a" In some formula I forgot it :/ wht does tht mean :/

Λ=ax/D
Λ=wavelength of the wave
a=slit separation
x=fringe separation
D=distance between screen and slit

 

[kitkat <3 :P]

Λ=ax/D
Λ=wavelength of the wave
a=slit separation
x=fringe separation
D=distance between screen and slit

Is the distance between slit n slit separation the same thing ?
Thanjs btw

 

[princeali97]

Is the distance between slit n slit separation the same thing ?
Thanjs btw

slit separation is the distance between the midpoint of two successive slits.
no problemo

 

[Ishrar Afrida]

http://onlineexamhelp.com/wp-content/uploads/2013/09/9702_s13_qp_12.pdf

can anyone help me with number 9? how is it 16000N?

 

[sameen saeed]

http://onlineexamhelp.com/wp-content/uploads/2013/09/9702_s13_qp_12.pdf

can anyone help me with number 9? how is it 16000N?

pressure=p(density) mutliply velocity^2 as u get the pressure use formula pressure mutiply area =force formula to get the right answer

 

[Batguy]

http://onlineexamhelp.com/wp-content/uploads/2013/09/9702_s13_qp_12.pdf

can anyone help me with number 9? how is it 16000N?

Hint:
try to convert things into Si units en make a formula of Kg/S
multiplying Speed , density , area gives u Mass /second units thats all wat u need!! Multiply all those quantities.......then put formula
F=ma
F=m*(v-u)/t (here just focus mass per unit time ,the answer u had before)
V (v=33)
f=475.2*(33) =15681.6 approx answer!!!
(D) answer
(i sick in teaching skills)

 

[Ishrar Afrida]

pressure=p(density) mutliply velocity^2 as u get the pressure use formula pressure mutiply area =force formula to get the right answer

Thanks sameen I just didn't know this formula!
And hey can you help me with number 14 as well?

 

[Ishrar Afrida]

Hint:
try to convert things into Si units en make a formula of Kg/S
multiplying Speed , density , area gives u Mass /second units thats all wat u need!! Multiply all those quantities.......then put formula
F=ma
F=m*(v-u)/t (here just focus mass per unit time ,the answer u had before)
V (v=33)
f=475.2*(33) =15681.6 approx answer!!!
(D) answer
(i sick in teaching skills)

I seriously didn't get you! why would I multiply everything randomly lol

 

[sameen saeed]

Thanks sameen I just didn't know this formula!
And hey can you help me with number 14 as well?

first of all convert the masses in kilograms to newtons as forces r in newtons then use the formula force * perpendicular distance to calculate moment of each force from pivot.Use idea sum of anticlockwise moment =sum of clockwise moment to calculate the remaining moment needed to balance.This will give u ans

 

[Faaiz Haque]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s10_qp_21.pdf

Q4 - B (Explain your calculations please)
Q4 - C


http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s11_qp_21.pdf
Question 7 C i and ii
Mark scheme just says correct lines labelled, lol.

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s10_qp_21.pdf

Q4 - B (Explain your calculations please)
Q4 - C


.

Answer was uploaded!

View attachment 40338

View attachment 40339

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s11_qp_21.pdf
Question 7 C i and ii
Mark scheme just says correct lines labelled, lol.

The question 7 is left, Suchal Riaz