Magnetic Forces and Magnetic Field

[aesura]

Homework Statement

A charged particle with a charge-to-mass ratio of |q| / m = 5.7x10^8 C/Kg travels on a circular path that is perpendicular to a magnetic field whose magnitude is 0.72 T.

How much time does it take for the particle to complete one revolution?

Homework Equations

errrr.. I have no clue where to start with

The Attempt at a Solution

:( :(

Thank you for your help...

 

[aesura]

*bump*

i tried to work it tho...not like I am just posting a new thread HEY GUYS COULD U PLEASE DO THIS FOR ME??

the trouble I am having is that I can't link t with all my magnetic formulas... and I've never heard of charge mass ratio...

i tried to work out hte velocity but... not enough data for it...

anyway physicists we need you!

 

[Suy]

F_m=qvB
F_c=(mv²)/r
because the particle is moving on a circular path,
so F_m=F_c
rearrange the formula to q/m=?, then solve for the radius
then use the radius to find the circumference,
d/t=v
where d is the circumference
Hope that helps

 

[aesura]

hmmm yea :( indeed... damn it... sorry I am med student not a physicist...

that was easy... :*( :*(

F = q v b sin 90
F = qvb

F = mv^2 / r ... obviously since a = v^2/r since it is a centri. force...

qvb = mv^2/r
q/m = v^2/rB
5.7x10^8 C/Kg = v/rB since v must be 2pi... :(


5.7x10^8 C/Kg x r = 2pi/0.72T

r = 1.53 x10^8 s

thank you so much... this is the correct answer... thanks heaps :)