Answer to Question #176088 in Electricity and Magnetism for Blank 0822

Question

Three charges were present inside the coil. The charges were labeled “a”, “b”, and “c”. Charge “a” has a value of 20µc, charge “b” has a value of -50µc and charge “c” has a value of 15µc. Each charge has a distance of 5m to each other. 

a. What is the total force between charges “a” and “b”?

b. What is the total force between charges “b” and “c”?

c. What is the total force and direction of the charges assuming that our charge “a” is the starting point?

Answer 1

Answer

Force between two charged particle

$F=\frac{kqq'}{r^2}$

a. Force between a and b charge

$F_{ab}=\frac{9\times10^9\times20\mu C\times50\mu C}{(5)^2}=0.36N$

b. Force between second and third charge

$F_{bc}=\frac{9\times10^9\times50\mu C\times15 \mu C}{(5)^2}\\=0.27N$

Now

c. Force between first and third charge

$F_{ac}=\frac{9\times10^9\times20\mu C\times15\mu C}{(10)^2}\\=0.027N$

So net force on first charge

$F_{a}=F_{ab}+F_{ac}$

$=0.36(i) +0.027(-i)$

$=0.33(i)$

In positive x axis.