00:01
Okay, so we know charge q can be equal to sigma times a.
00:04
Sigma is the surface charge density, and a is the area.
00:08
And we know the area of the cylinder is equal to 2 pi r times l plus r.
00:13
And r is the radius, l is the length of the cylinder.
00:16
Okay, so therefore q is equal to sigma times 2 pi r times l plus r.
00:20
And the surface charge density is given as 15 nanocouon per meter square, which is about 15 times 10 to the power of negative 9 a koolong per meter square.
00:30
And r which is the radius is given as 2 .5 centimeter which is 0 .025 meter and the length of a cylinder is 6 centimeter which is 0 .06 meter.
00:40
So therefore charge q is equal to 15 times 10 to the power of negative 9 cologne and then times 2 pi times 0 .025 meter and then times 0 .025 meter and then times 0 .025 meter plus 0 .06 meter and this will give us the charge is about 2 times 10 to the power of negative 10 kool -on for this case.
01:26
Okay? for the next question, you was asking us about the amount of charge on its curve lateral surface...