John and Barry are pulling on a fence post with ropes while their friend Pat uses a chain-saw to shear it at ground level. John applies a force of 75.0 N [40 degrees] on one rope while Barry applies a fore of 85.0 N [340 degrees] on the other rope. What is the net force on the post?

What is a subatomic particle with a negative charge and very little mass?

Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.

Ascientist wants to test ways to reduce pollution in lake . what is the bestway of doing this