Physics: Post your doubts here!

[ahmed abdulla]

a=2.8(check the graph)
m nt good at this part but i will try
frm its max amp to b the phase difference is 90 and fr a to max the phase difference is 1/2 of 90
so phase diff is 135

thanks ... if some one has a better idea .....any help ???

 

[Alool]

Can someone please help me with this question?
this is from M/J 2008 p2

 

[Warrior66]

A

ok..so i tried it again and i happen to get A as well..here's my explanation:
basically what we do is we use all the vectors given to make a closed triangle since the question tells us that the object is in equilibrium.

so now you try out all the options with the triangle above and you find out your answer is A.

 

[Tkp]

Can someone please help me with this question?
this is from M/J 2008 p2

for the first 1 p=v^2/r(put the value of v and p which is in kw)
fr 2nd 1 when s1 is open and s2 and s3 is closed then the power would be zero due to the open of s1.
when s1 and s2 closed and s3 open then the power would be 1.5 becz due to the close of s2 so the power would be 1.5
when 3 of them are closed then the total power is 3 becz due to the close of s2 we get 1.5 and through s3 its 1.5 so total is 3
when s1 closed and s2 and s3 open then the power would be 0.75
s1 closed s2 open s3 closed,so the power of s3 is 1.5 and due to the open of s2 the power would be 0.75
s0 total power is 2.25

 

[Minato112]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/
Plz someone help me with question 5 part c.... thnks

hmmm srry I cant find part c.... s (b) (ii) is the last part...

 

[abcde]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s12_qp_42.pdf
Q10. (b) (i) (ii) Why isn't the negative sign in the formula used in the (m.s.) calculation of the ratio?
http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s12_ms_42.pdf

 

[Dug]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s12_qp_42.pdf
Q10. (b) (i) (ii) Why isn't the negative sign in the formula used in the (m.s.) calculation of the ratio?
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s12_ms_42.pdf

They just rearranged the formula using simple math.
e⁻¹ = 1/e

 

[abcde]

They just rearranged the formula using simple math.
e⁻¹ = 1/e

Thanks. I didn't see that.

 

[hellangel1]

Is anyone else struck in the topics 'Circular motion' and 'gravitational field' in A2 physics?
any help or notes plz

 

[hellangel1]

Im stuck at the A2 topics 'Circular motion' and 'Gravitational fields'
Any help please?

 

[ahmed abdulla]

any help with phase difference ...? second time posting about this ....plz help
when they say another wave has phase fifference 90 .. how to draw it ..... and how to find phase difference betwween two points

 

[VelaneDeBeaute]

any help with phase difference ...? second time posting about this ....plz help
when they say another wave has phase fifference 90 .. how to draw it ..... and how to find phase difference betwween two points

You shift the same wave 90 degrees ahead!

 

[sweetsis]

hey can somebody please explain phys mcq 30 and 31 from wo3..

 

[VelaneDeBeaute]

hey can somebody please explain phys mcq 30 and 31 from wo3..

Link?

 

[leosco1995]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s09_qp_4.pdf

Q6 (b) (i) State and explain the polarity of the pole P of the magnet.

How do you figure this out? :s

 

[ahmed abdulla]

You shift the same wave 90 degrees ahead!

can u be more clearer please ... a diagrm will be better

 

[A*(a*)]

can someone help me pleasssseeee?

 

[Minato112]

can someone help me pleasssseeee?View attachment 23499

Answer B. Acceleration is given by the gradient of a velocity-time graph. You have to look at the gradients of the 4 graphs and you will notice that the graph in B corresponds to it. Let's analyse it. Split the graph (in A) into 3 parts. First you notice that the gradient increases implying that acceleration increases. Then the gradient becomes zero ===> that acceleration is now on a horizontal point. Finally, when the velocity decreases, the gradient decreases and thus the acceleration decreases.

Note : I did this in a real hurry. Please check the answer mayB I didn't read the question correctly.

 

[A*(a*)]

Answer B. Acceleration is given by the gradient of a velocity-time graph. You have to look at the gradients of the 4 graphs and you will notice that the graph in B corresponds to it. Let's analyse it. Split the graph (in A) into 3 parts. First you notice that the gradient increases implying that acceleration increases. Then the gradient becomes zero ===> that acceleration is now on a horizontal point. Finally, when the velocity decreases, the gradient decreases and thus the acceleration decreases.

Note : I did this in a real hurry. Please check the answer mayB I didn't read the question correctly.

Yes thats exactly what I thought but the answer to our misfortune is A! B looks so possible.

 

[Areeba Shahnawaz]

View attachment 23390

1200-800=200a
a=2m/sec
2as=V2-U2
2.2.9=V2
V=6m/s
(we took distance 's' as 9 bcuz at half distance, the man's head iz level with bottom of barrel )