An object with a potential energy of 981 J is placed at a height of 2m. What is the mass of the object?

the mass of object is 2000

a charge 3q is at the origin, and a charge −2q is on the positive x axis at x=a. part a where on the x-axis would you place a third charge so it would experience no net electric force? enter an expression for the exact answer, which will involve a square-root sign. (do not enter an approximate decimal answer.)

vapour or gas assuming atmospheriv pressure