# physics

posted by .

Three charges sit on the vertices of an equilateral triangle, the side of which are 30.0 cm long. If the charges are A = +4.0 C, B = +5.0 C, and C = +6.0 C (clockwise from the top vertex), find the force on each charge.

• physics -

Charge A(q1)
F12 = k•q1•q2/a².
F13 = k•q1•q3/a².
F(A) = sqrt(F12² + F13² - 2•F12•F13•cos 120º).

Charge B(q2)
F21 = k•q1•q2/a².
F23 = k•q2•q3/a².
F(B) = sqrt(F21²+F23²-2•F21•F23•cos120º).

Charge C (g3),
F31 = k•q1•q3/a².
F32 = k•q2•q3/a².
F(C) = sqrt(F31² + F32² - 2•F31•F32•cos 120º).

• physics -

How did you get F12 and F13 ??

• physics -

physics - sara, Friday, August 17, 2012 at 10:45pm
How did you get F12 and F13 ??

F12 = k•q1•q2/a²=9•10^9•4•10^-6•5•10^-6/0.09=2 N
F13 = k•q1•q3/a² = 9•10^9•4•10^-6•6•10^-6/0.09=2.4 N

F(A) = sqrt(F12² + F13² - 2•F12•F13•cos 120º)=
=sqrt[4+5.76-2•2•2.4(-0.5)] =3.82 N

## Similar Questions

1. ### Physics

Mass 1 (10 kg) rests on a table connected by a string to Mass 2 (5 kg). If s = 0.30 and k = 0.20, what is a) the acceleration of each block?
2. ### computer science

. Investigate the values of  and  such that the system of equations x + y + z = 6 x + 2y + 3z = 10 x + 2y + z = , may have (i) Unique solution
3. ### stat

7. A researcher selects a random sample. A 90% confidence interval for a population mean  A) is an interval with margin of error ± 90%. B) has the property that if we repeatedly selected our random sample in exactly the same …
4. ### physics

Consider a charge of +2.0 C placed at the origin of an X-Y co-ordinate system and a charge of -4.0 C placed 40.0 cm to the right. Where must a third charge be placed – between the charges, to the left of the origin, …
5. ### physics

If the electric potential energy between two charges of 1.5C and 6.0 C is 0.16 J, what is their separation?
6. ### physics

A +5.7 C and a -3.5 C charge are placed 25 cm apart. Where can a third charge be placed so that it experiences no net force?
7. ### physic

3 charges sit on vertical equilateral triangle the side of each is 30.0 cm. if the triangle are A= +4.0 uC B=+5.0 uC and C=+6.0 uC (clockwise from top) what is the force on each charge?
8. ### Physics

3 charges sit on vertical equilateral triangle the side of each is 30.0 cm. if the triangle are A= +4.0 uC B=+5.0 uC and C=+6.0 uC (clockwise from top) what is the force on each charge?
9. ### Statistics

To test H0:  = 80 versus H1:  < 80. a simple random sample of size n = 22 is obtained from a population that is known to be normally distributed. a) If ¯x = 76.9 and s = 8.5, compute the test statistic.
10. ### Physics

Sphere A, with a charge of +64 C, is positioned at the origin. A second sphere, B, with a charge of -16 C, is placed at +1.00 on the x-axis. Where must a third sphere, C, of charge +12 C, be placed so that there …

More Similar Questions