A uniformly charged disk of radius 20 cm carries a charge with a density of 6 nC/m². The electric field (in N/C) on the axis of the disk at 8 cm from the center of the disk is:​

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

it doesn't. it was imagined up in the middle ages.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west