99 Taurus right wheel makes a soft plop or bumping sound when I go over uneven road, what is it?

does it happen when you turn too? My thought would be a ball joint. Jack up that wheel off the ground and see if you can rock the wheel in any direction. Have a buddy look at the componants while you rocking the wheel. you will be able to notice if any thing is moving. any of these parts(ball joint, strut, or mount) will be under $100 for parts and anybody with a little knowledge can fix them.