ALL PHYSICS DOUBTS - POST HERE !!

[winnie101]

could someone plz explain to me ques. 5,7,15,18,20,and 29 form m/j 2009 paper 1 physics cie AS level
Thanks

[Snake]

could someone plz explain to me ques. 5,7,15,18,20,and 29 form m/j 2009 paper 1 physics cie AS level
Thanks

Wrong place to post I think. Post your question again here https://studentforums.biz/index.php/board,82.0.html

[Snake]

That is correct.

So why do they use 0.5AT^2? maybe he confused it with 0.5MV^2 (For Kinetic Energy)?
Woo Now I'm confused :S

[nid404]

So why do they use 0.5AT^2? maybe he confused it with 0.5MV^2 (For Kinetic Energy)?
Woo Now I'm confused :S

huh?

distance is given by ut+1/2at²

k.e= 1/2 mv²

[nid404]

Can any1 plz explain the thermal expansion? And What expands more.. solids, liquids or gases and why? Thanks in advance

Thermal expansion is a lot in itself.

http://www.docbrown.info/page03/3_52states.htm   excellent stuff.

[Hesham Mhd]

srry but, i did find nthn about the expansions O_o, can yu just expain it on here in brief plz?

[nid404]

ohk...you wanted to know how they expand relatively right.

solids<liquids<gases

What else do you want to know..?

if you put pointers from the syllabus, it'll be easier for me

[Hesham Mhd]

um ok, 'Describe Qualitatively the thermal expansion in solids, liquids and gases' ?

[nid404]

Please go through the link I provided. It explains thermal expansion well...

[holtadit]

um ok, 'Describe Qualitatively the thermal expansion in solids, liquids and gases' ?

In short:

solids have strong electrostatic bonds between particles that prevent them from expanding too much.

liquids have slightly weaker bonds and can expand a bit more

gases have NO forces of attraction and can expand to fill up container and exert GREATER pressure when heated.

[Hesham Mhd]

Thanks alot dude, and, can yu explain the thermal expansion in terms of molecules?

[holtadit]

Thanks alot dude, and, can yu explain the thermal expansion in terms of molecules?

As the temperature rises the kinetic energy of the molecules increases as they begin to vibrate faster. Some of this energy is used to increase the spacing between individual molecules leading to expansion of material.

[Hesham Mhd]

Thanks alot!, yu really cleared this 4 me.
And, if we have a converging lens, when will it form a magnified, virtual image? and when will it form a real, upside-down image?

[holtadit]

magnified, virtual = object is closer to the lens than the focal length.

real, upside down = every other position except the one above.

[Hesham Mhd]

Really Thanks, yu've got some reputation added