00:01
Hi, here for the given question, we know that the equation of the sphere centered at origin with radius 2 can be given as x square plus y square plus z square is equal to 4, 2 square which is equal to 4.
00:15
Now here if we parameterize the surface a's with a spherical coordinate, here we have x is equal to r times sine of y multiplied with cos theta, y is equal to r sine of y multiplied with sine theta and here we have z is equal to r cos of y.
00:35
So here we have 0 less than or equal to 5 less than or equal to pi and 0 less than or equal to theta less than or equal to 2 pi.
00:42
So here in our case now further we know that the outward unit normal vector of the sphere is simply the normalized position vector pointing away from the origin.
00:55
So n is equal to x comma y comma z divided by 2.
00:59
So this is the value of n vector.
01:02
Now further here in our case we need to calculate what is the value of the flux.
01:06
So here flux can be calculated as double integration over s f dot ds is equal to double integration over s f dot n ds.
01:16
So here in our case now further we are given that f is equal to y comma minus x comma 2z.
01:23
So here taking the product of f dot n here we have y comma minus x comma 2z multiplied with n which is x comma y comma z divided by 2.
01:35
So here on simplifying this we have f dot n is equal to xy by 2 minus xy by 2 plus 2z square upon 2.
01:49
This cancels each other so we have f dot n is equal to 2z square upon 2.
01:54
2 and 2 cancels each other so we have z square.
01:56
So here substituting the value in our above integral we have double integration over s f dot ds is equal to integration over 0 to 2 pi integration over 0 to pi and here we have z square multiplied with r square sine of pi d pi and d theta and here for r we have value of integral from 0 to.
02:20
So here further here in our case we can say that by integrating this terms here we have value of integral as integration over 0 to 2 pi as it is integration over 0 to pi as it is...