Edexcel PHYSICS Doubts

[Deadly_king]

Hey Everyone ...Well I have a Doubt .....Can someone give me notes or a Website that has notes on Fluid Flows ...The teacher just taught us some of the basics And the whole time I was -__-  cuz i didn't get it :S :S

Thank You In Advance

Am not sure about it myself. So i'll ask you to consult your syllabus before proceeding to this link.

http://www.engineersedge.com/fluid_flow/fluid_flow_table_content.htm

[The Golden Girl =D]

Hmm Okay I'll get my copybook and start studying from it if i find any doubts I'll take a pic and post it

Thanks but the thing obviously freaked me out :S

[blackberry]

so i was just trying to study physics today and then WHAAAM!!! i got stuck at this point where my textbook mentioned that in hooke's law(F=kx) the spring constant(k)represents the 'stiffness' of the spring and then in another textbook it mentions that the young modulus(E)of a material is a measure of how stiff it is!! 
so i assumed that k = E, considering that both measure the stiffness of the material and both are found using the gradient of F/x graph in the case of k and Stress/Strain graph in the case of E.
BUT.....i think my teacher told me that they are both different, so im kinda confused as to which is what so can anyone tell me the difference between spring constant and young modulus please??   

[elemis]

The spring constant is true for a spring of a particular dimension ONLY.

The YM is true for a PARTICULAR material no matter what dimensions it takes in a particular spring.

[blackberry]

urmm?

[The Golden Girl =D]

so i was just trying to study physics today and then WHAAAM!!! i got stuck at this point where my textbook mentioned that in hooke's law(F=kx) the spring constant(k)represents the 'stiffness' of the spring and then in another textbook it mentions that the young modulus(E)of a material is a measure of how stiff it is!! 
so i assumed that k = E, considering that both measure the stiffness of the material and both are found using the gradient of F/x graph in the case of k and Stress/Strain graph in the case of E.
BUT.....i think my teacher told me that they are both different, so im kinda confused as to which is what so can anyone tell me the difference between spring constant and young modulus please??   

Look when you draw a force-extension graph ,the gradient represents the stiffness of the material . the STEEPER the gradient is the STIFFER it is and since stiffness is the gradient it's calculated as follows :

Stiffness/Gradient = Force/Extension

Young Modulus is the MEASUREMENT of how stiff the  material is and

YM = stress/ strain

YM= (f/a) divided by (x/l)

hence , YM = (f/x) * (l/A) -> Pascals

If you don't get it , let me know

[elemis]

urmm?

If i have a 10 cm long steel wire of 1mm² cross sectional area the way it behaves under a load will differ from a 20 cm long steel wire of 0.5 mm²

This difference in behavior i.e. extension will affect the Spring Constant of the springs. That is, the first wire will have a different SK from the second one.

However, with the Young's Modulus we compare the stress and strain of the steel wire. Incidentally the YM of both wires will be the SAME.

[The Golden Girl =D]

I assume he Understood , well still if u don't get it let us know mate

[blackberry]

oooooooooooooooooooooooooooooohhhhh nowww i get it!!!!
By the way golden girl im a she not a he!!

nyywayyy thanxxx so much guys!!!!gosh physics is reallly mind-boggling!!!

[The Golden Girl =D]

oooooooooooooooooooooooooooooohhhhh nowww i get it!!!!
By the way golden girl im a she not a he!!

nyywayyy thanxxx so much guys!!!!gosh physics is reallly mind-boggling!!!

glad u do
my bad 

It's NOT once you get it

[blackberry]

u noe i only have such problems with physics no other subjects!!
oo hey i got nother question!!
could u plzz temme bout acceleration of free fall with and without air resistance??
i keep getting confused bout the acceleration part! 

[elemis]

Acceleration under gravity in a vacuum without air resistance means the object will fall with a constant acceleration 9.81 ms^-2

[blackberry]

so just at the point the object is dropped will g=9.8 or 0
and while it is falling is it accelerating or decelerating??
what is the situation with air resistance??
and how exactly would the graph of velocity against time for both cases come out??

(Sorry for the 1000000000 questions i just get confused when i try to understand and concentrate on things alot plus i have a baad case of amnesia(not literally)!!!! )

[The Golden Girl =D]

so just at the point the object is dropped will g=9.8 or 0
and while it is falling is it accelerating or decelerating??
what is the situation with air resistance??
and how exactly would the graph of velocity against time for both cases come out??

(Sorry for the 1000000000 questions i just get confused when i try to understand and concentrate on things alot plus i have a baad case of amnesia(not literally)!!!! )

through out  the whole free fall the Acceleration is 9.81

what changes is the SPEED

speed decreases going down due to air resistance due to the formula :

Air resistance is directly proportional to Square Speed  *meaning speed to the power of two *

I'm sorry but if u are doing AS physics Edexcel Unit One , You don't need to know that cuz the air resistance is ALWAYS there . Unless it is stated in the Q that it is negligible .

I'm sorry but I don't know it or perhaps I'm too sleepy to focus -.-

[The Golden Girl =D]

try these links ,cuz u might need them :

http://www.physicsclassroom.com/class/newtlaws/u2l3e.cfm