Physics Corner

[MH-UK]

Just for fun, derive F = BQv from F = BIl

 

[lolwatever]

lol i havnt done electromagnetism for agesss....

but it goes along these lines.. i think .. lol

B = F/Il
F = IlB sin(theta)

we know that Il = qvl/l = qv, i think its coz Il is current element for a stream of particles.. so u got like this bunch of particles passing at a rate 'l per second' which can be expressed as 'v/l'.... sooo the current in that length is qv/l... therefore teh current element is Il=qv/l=qv...

substituting that ...

we get F = qvBsin(theta)

 

[MH-UK]

Yes.

F = BIl

Q = It
charge = current x time
Rearranging ... I=Q/t

v = l/t
velocity = displacement/time
Rearranging ... l = vt

Substituting into F = BIl gives F = B x Q/t x vt

The t's cancel leaving F = BQv and one can put the sin theta's on the ends.

 

[MH-UK]

Just for fun derive F = V/d from F = E/Q insha'Allah.

 

[Ameeratul Layl]

I was parcitsing subsituting,yesterday. that isn't a problem - I don't think. I still remember some of the formaules:

D=ST
V=IR
a=U-V/T
S=UT+0.5at(squared)
Q=IT
P=IR (I think)
Knetic energy = 0.5mv(squared)

em...that is it I think.


lolwatever, I do not understand your table. It is a little confusing. But thank you.:sister:

 

[Ameeratul Layl]

Salam,

F=MA
W=MG

Never forget those ones.

Wasalam

 

[lolwatever]

I was parcitsing subsituting,yesterday. that isn't a problem - I don't think. I still remember some of the formaules:

D=ST
V=IR
a=U-V/T
S=UT+0.5at(squared)
Q=IT
P=IR (I think)
Knetic energy = 0.5mv(squared)

em...that is it I think.


lolwatever, I do not understand your table. It is a little confusing. But thank you.:sister:

lol sis np.. ill try xplain it again:

kilo-----hecta----deca----units-----deci-----centi-----milli
10^3---10^2 --- 10 -------1------10^-1----10^-2-----10^-3
km------hm------dam--------m-------dm-------cm------mm---------distance


units represents the 'standard unit' metre for example.. so if u wanna go from decimeter to metre, 1dm = 10^-1m.... whereas 1mm=10^-3 m...

u got thigns like nano.. 1nm=10^-9... and micro 1micrometer = 10^-6 etc..

basically that table represetns each unit in terms of the standard 'fundametnal unit' (the metre)

same goes for the detailed tabel in the 2 post above.. represetns volume interms of stadnard unit (L) and mass in terms of standard unit (kg)..

lol sorry if its not too much help..
salamz

 

[lolwatever]

Salam,

F=MA
W=MG

Never forget those ones.

Wasalam

to make life easier, just remember F=ma.. it's exact same thing as W=mg
its just that F=W, a=g=9.8...
salamz

 

[Ameeratul Layl]

lol sis np.. ill try xplain it again:

kilo-----hecta----deca----units-----deci-----centi-----milli
10^3---10^2 --- 10 -------1------10^-1----10^-2-----10^-3
km------hm------dam--------m-------dm-------cm------mm---------distance


units represents the 'standard unit' metre for example.. so if u wanna go from decimeter to metre, 1dm = 10^-1m.... whereas 1mm=10^-3 m...

u got thigns like nano.. 1nm=10^-9... and micro 1micrometer = 10^-6 etc..

basically that table represetns each unit in terms of the standard 'fundametnal unit' (the metre)

same goes for the detailed tabel in the 2 post above.. represetns volume interms of stadnard unit (L) and mass in terms of standard unit (kg)..

lol sorry if its not too much help..
salamz

No, sorry for being so difficult.
Is the ^ meant to be the EXP sign?

 

[Ameeratul Layl]

to make life easier, just remember F=ma.. it's exact same thing as W=mg
its just that F=W, a=g=9.8...
salamz

I know that. I just forgot to add them to the list.

 

[lolwatever]

oh that just indicates that the numbers next to it are "superscript"...

isntead of me sayign 10 to the power of -2
i say 10^-2

^= to the power of

maybe that was the confusing thing?
salamz

 

[Ameeratul Layl]

oh that just indicates that the numbers next to it are "superscript"...

isntead of me sayign 10 to the power of -2
i say 10^-2

^= to the power of

maybe that was the confusing thing?
salamz

Yes, that was the only confusing thing.
On the scientific calculator, I would press:

1.35 EXP -3

The ^ sign was a little confusing but it makes sence now.

JazakAllah.

 

[lolwatever]

in "real math" exp repersents "e to the power of"

e.. the base of the natural log...

so when i say exp(10).. that really means e^10

but yeh unfortunately some scientific calculators are evil.. they use exp to represent powers ffended: lol

 

[Ameeratul Layl]

in "real math" exp repersents "e to the power of"

e.. the base of the natural log...

so when i say exp(10).. that really means e^10

but yeh unfortunately some scientific calculators are evil.. they use exp to represent powers ffended: lol

Yes, I agree.

What is hecta?

:raging: I'm confused again!

Lolwatever, is there nothing simpler than your table?:sister:
My sheet of convesrtions looked nothing like that.
Im sorry for being really difficult.
You don't have to reply if you feel there is no simpler way to put the conversions. I understand.

 

[lolwatever]

there's this other way personally i hate it... but some people seem to fall in love with it quickly, ill find it n get bak2u in a couple hours inshalah... not on me at the moment.
tc
salamz

 

[lolwatever]

^^ in the mean while, there's this nifty little thing i found:

http://www.chemie.fu-berlin.de/chemistry/general/units_en.html

unit converter
salamz

 

[Ameeratul Layl]

there's this other way personally i hate it... but some people seem to fall in love with it quickly, ill find it n get bak2u in a couple hours inshalah... not on me at the moment.
tc
salamz

JazakAllah.

 

[Ameeratul Layl]

Here is a question for vectors:

Q1. A car is being towed with a rope inclined at 20 degrees to the horizontal. The tension in the rope is 350N.
Work out the horzontal and verical components of the tension in the rope.

Just a quick question: Could you remind me of the Tension equation. The one in the book looks too...complicated.
JazakAllah.

 

[MH-UK]

Horizontal : (350cos20)N
Vertical : (350sin20)N

 

[MH-UK]

This may help explain above post