Physics help!

[cooldude]

yeah I figured that....didn't really notice what they were asking for. 

Ah...one more question

June 2010 paper 4 variant 1, Q3 b) How can they say acceleration is constant ? :S Is it because a=g ?

yeah in a way, well the component of the weight that acts down is mgsinx, let x be the angle between the inclined plane and the ground, so mgsinx=ma
so a=gsinx, x is the same for both and g is a constant therefore the acceleration is constant and therefore it cant be shm as a varies with the displacement

[nid404]

yup component of g I meant...ohk just confirming...thanks 

[nid404]

With reference to capacitors, can someone explain what 'smoothing' is?

[M-H]

Yeah capacitors smoothen AC.  As in think of it, the capacitor is charged during the positive cycle, while it discharges during the negative cycle. the discharging and charging takes up time...that way, the discharging and charging do not happen at equal intervals..eventually, a graph that would be normally with distinct waves, with a capacitor, you can see it becoming for even.

Sorry, this is a rough explanation. hope it helped.

[nid404]

Uhm...Can you get me a graph please  Visualizing this is beyond the capacity of my cat brain  Physics doesn't go well with me 

[nid404]

And yes Where can I find notes on Application of Physics?

I DO HAVE the CIE Application Booklet for reference(which is pretty useless)

Thank you

[M-H]

i'll try to get you sth!! haha, its okay! cat brains

Hey, what i usually do for finding out about the applications- i look it up on wikipedia!
Like for capacitors, one important application is, charged coupled devies...so just find out and they explain how the actual thing happens!

[nid404]

Wikipedia ahan...okay I'll go through..thanks 

[M-H]

http://www.kpsec.freeuk.com/powersup.htm#smoothing

[M-H]

Hey, the only difference between the things mentioned in the link i provided and AC, is, that AC have both negative and positive cycles. During the positive cycle, a capacitor is charged, but during the negative, it discharges. 

[nid404]

Well smoothing is the same as having a rectifier with capacitor filter right?

[M-H]

No a rectifier would cut the negative cycles. Its the time that's taken up by the discharging and charging that makes the time interval different, and therefore, your wave is not the same as before. it would become less steep. Eventually, by becoming more and more shallow, its becoming smooth and even!

[nid404]

Uhm...if it's an alternating current, the graph would be different. The graph you showed me is one with a full wave rectifier and a capacitor filter.

[M-H]

Urgh...i...

Alright..i'll look for something to explain my bit hopefully soon!

[nid404]

I've figured it...thanks for your help though