Two identical small spherical conductors (point charges), separated by 0.6 m, carry a total charge of 200 mu or micro CC. They repel one another with a force of 120 N. (For the universal constant k use the value 8.99 times 109 N m2/C2.)
I think i am suppose to use E=kQ/r^2 . do I use this for both spheres then add them to equal 200? where does the force come in?
4 answers
(a) Find the charge on each sphere.
E is the electric field, the force on a point charge of ONE coulomb.
You can do it with E for either charge, ten multiply by the charge on the other (the target) sphere.
Normally though you would just use the Coulomb law form
F = k Q12Q2/r^2
see:
http://teacher.nsrl.rochester.edu/phy122/Lecture_Notes/Chapter22/Chapter22.html
You can do it with E for either charge, ten multiply by the charge on the other (the target) sphere.
Normally though you would just use the Coulomb law form
F = k Q12Q2/r^2
see:
http://teacher.nsrl.rochester.edu/phy122/Lecture_Notes/Chapter22/Chapter22.html
call one charge Q1 and call Q2 = (200*10^-6 - Q1)
Use the formula F=kQ1Q2/r^2.
Q1+Q2=200*10^-6 C
200*10^-6 C - Q1=Q2
substitute Q2 into the top formula and solve the equation.
Q1+Q2=200*10^-6 C
200*10^-6 C - Q1=Q2
substitute Q2 into the top formula and solve the equation.
2 answers