00:01
So, first of all, we will write the given part according to the question.
00:04
So, the charges on the spheres, let us say q1 is equal to 6 microcoulomb according to the question.
00:12
And charge on the another sphere, let us say it as q2, it is 18 microcoulomb.
00:18
Okay.
00:18
So, we know that when two spheres are in contact, their potential difference is equal.
00:46
So, we can say let q1, capital q1, okay, and capital q2 are the new charges.
00:59
So, when they are brought in contact, we can say that the potential differences will be equal.
01:07
Okay.
01:08
So, we can say that q1 upon c1, because we know that q is always equal to cv.
01:14
Okay.
01:14
We know this formula.
01:16
So, here we can write v as q upon c.
01:18
So, the new charge will be capital q1.
01:20
So, capital q1 upon c1 upon, sorry, equal to the value of v2 will be equal to capital q2 upon c2.
01:30
Okay.
01:30
So, if we find the value of capital q1 upon capital q2, it will be equal to c1 upon c2.
01:36
Okay.
01:37
Now, the value of c1 will be 4 pi epsilon0 r1.
01:42
Okay.
01:43
And the value of c2 will be 4 pi epsilon0 r2.
01:47
Okay.
01:48
So, this is the value of c1 and c2 here.
01:53
So, if we cancel the terms, then it will be equal to r1 upon r2.
01:58
And according to the question, we have already given that the size of the second sphere, which is r2.
02:06
Okay.
02:06
So, its radius is equal to the double of the first sphere...