Question

Two positive charges 12×10^-6C and 8×10^-6 are 10cm apart. Find the workdone in bringing them 4cm together

Answer 1

W = 5.76 J

Step-by-step explanation:

Given that,

Charge 1,
`q_1=12* 10^(-6)\ C`

Charge 2,
`q_2=8* 10^(-6)\ C`

The distance between charges is 10 cm.

Initial distance = 10 cm = 0.1 m

Final distance = 10 cm - 4 cm = 6 cm = 0.06 m

We need to find the work done in bringing the 4 cm together.

We know that,

Work done = change in kinetic energy

`W=kq_1q_2((1)/(r_2)-(1)/(r_1))\\\\\text{Put all the values}\\\\W=9* 10^9* 12* 10^(-6)* 8* 10^(-6)((1)/(0.06)-(1)/(0.1))\\\\W=5.76\ J`

So, the required work done is 5.76 J.