Arock is whirled around in a circle with a slingshot. as the rock leaves the slingshot, it has an instantaneous velocity in a straight line. how do newton's laws of motion explain this?

D)To move in a circle requires an acceleration and therefore a net force. This force is supplied by the slingshot.

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. 

the higher the current the higher the mag field around it the higher the influence on the compass