00:01
So it is given to us in the question that the spheres have a charge of q1 equals minus 3 multiplied by 10 raised to minus 6 coulum and another sphere has a charge of q2 equals 2 multiplied by 10 rise to minus 6 coulum.
00:22
Now they are separated by a distance of r equals 0 .01 meter.
00:30
Okay, now we have to find the force that is acting between them, then the force that is acting between them would be equal to k multiplied by q1, q2, divided by r square.
00:44
Okay, now what is k? the value of k is 9x multiplied by 10 raise to 9 newton meter square per coulum square.
00:55
Okay, now substituting these values in this equation we get, 9 multiplied by 10 raised to 9, multiplied by minus 3 multiplied by 10 rise to minus 6, multiplied by 2 multiplied by 10 raise to minus 6, divided by 0 .01 the whole square.
01:21
Okay.
01:22
On simplifying this, we get the answer as minus 540 newton.
01:28
Okay, this negative sign indicates that the force is attractive in nature.
01:36
Okay, so this is attractive force.
01:39
Now coming to the second part of the equation, that is the b part, the spheres are brought into contact with each other.
01:46
Now if the spheres are brought into contact with each other, then the charge will be shared between the two spheres.
01:53
That is, each sphere has the same amount of charge.
01:56
So the charge on the spheres when they are brought into contacts would be equal to q1 plus q2 divided by 2.
02:08
And on substituting the values we get minus 3 multiplied by 10 raised to minus 6 plus 2 multiplied by 10 raised to minus 6 divided by 2...