The Ultimate AS Physics Thread

[WannaGoodGrade]

Nov 09

Question 3 ( ii )

and I can't understand J09 Q5


Any Help ??

 

[AlyHamza]

Nov 09

Question 3 ( ii )

and I can't understand J09 Q5


Any Help ??

Tell the variants of the papers........

 

[WannaGoodGrade]

Variant 1

 

[AlyHamza]

Variant 1

Refer to their marking schemes and examiner reports....... u'll understand they're not too difficult.
but still if u have any queries abt concepts/understandings do ask!

 

[beststriker]

Please help in Nov07/02, q5 a) part. How we can show the phase difference between two waves that is 60 deg...????

 

[yubakkk]

thanks zenzenzen

 

[hassam]

hmm......well if increasing slit width broadens the fringes then y brightness increase cos it shud decrease due to redistribution of energy over a wider area

 

[hassam]

why the brightness decreases when the wavelenght increases ?????????????????????????????

It doesn't! It only increases if you increase intensity or increase the separation of the slits! Or use a brighter light

v=fλ so f= v/λ . λ is increased, so f is decreased. Use Intensity is directly proportional to (frequency)^2 also. Intensity is decrease, brightness is decreased.

Also boz increasing the wavelength means fringe separation (x) has increased so for wider fringes the energy of light wave is redistributed. the same energy which was illuminating a smaller area is now illuminating a larger area so the fringes will be less bright.

Note: u wud be thinking that intensity is directly proportional to (amplitude)^2......... yes it is...... but it is also to (frequency)^2.

Hope this clears all ur misconceptions.........

u said FRINGE SEPARATION INCREASED......NOT fringe WIDTH.....but in very next line u said fringes became wider..i m confused. cn u clear me up why fringe became broader.......?

 

[yubakkk]

what will be the minimum mark for grade A in physics in total 140 mark in as level?
can any one guess???

 

[hassam]

105

 

[AlyHamza]

@Hassam

Fringe separation is the distance between the midpoints of two adjacent bright fringes (or two adjacent dark fringes). So when this distance is increased so will the fringes become wider too. Try visualizing this on a continuous spectrum of alternate bright and dark fringes. When fringes become wide so does their separation increase.

NOTE: By fringes becoming wide/broad i mean that their length increases along y-axis i.e. vertically.

 

[AlyHamza]

Please anyone: Q.3 (c) of Oct./Nov. P-2 (22) [9702/22/O/N/09]

 

[Zenzenzen]

Please anyone: Q.3 (c) of Oct./Nov. P-2 (22) [9702/22/O/N/09]

(i):
since maximum height is 0.98m, v = 0 at max height
v^2 = u^2 + 2as
0 = u^2 + 2(-9.81)(0.98)
u = 4.4 ms-1

(ii):
1.
From the problem part we know that the velocity with which ball hits the floor is 6.2 ms-1
From the previous part the velocity with which ball leaves ground is 4.4
We take one of the velocities (doesnt matter which) as negative because it is in the opposite direction
Δp = mv - mu
Δp = (.034)(4.4) - (.034)(-6.2)
Δp = .36

2.
We need to find out the force, and we know the change in momentum as well as the time with which the ball is in contact with the ground.
F = (Δp / Δt)
F = (.36 / .12)
F = 3 N

 

[beststriker]

Please Anyone help in Nov07/02, q5 a) part. How we can show the phase difference between two waves that is 60 deg...????

 

[Ash1994]

http://www.xtremepapers.me/CIE/Internat ... 8_qp_2.pdf

Hey can anyone help me (in abit of detail) on Q6 part b

 

[WannaGoodGrade]

Variant 1

Refer to their marking schemes and examiner reports....... u'll understand they're not too difficult.
but still if u have any queries abt concepts/understandings do ask!

I did.... but didn't understand it

 

[WannaGoodGrade]

Guys any one have a sheet for AS physics Rules ??

 

[JustinCredible]

CAn any1 please help me with Q3 part b and c of M/J/10/22.
Please explain the relationship, and y the graph will need to go to 5ms-1
http://www.xtremepapers.me/CIE/Internat ... _qp_22.pdf
Also, please explain q6 part b i), of the following paper
http://www.xtremepapers.me/CIE/Internat ... _qp_22.pdf

 

[WannaGoodGrade]

Also Yes i wanna know the June 09 V1 Q1 b ... Calculating uncertainty by the % method as given in mark scheme

 

[Saturation]

Also Yes i wanna know the June 09 V1 Q1 b ... Calculating uncertainty by the % method as given in mark scheme

I'd say use the Extreme values method for uncertainty! It saves time and is easier (atleast for me )