What is the electric potential vtot at the center of the square? make the usual assumption that the potential tends to zero far away from a charge. express your answer in terms of q, d, and appropriate constants?

15. give an example for some particles or waves that are moving faster than light in everyday life 16. what is a laser? 17. what is an oscilloscope? 18. what does it means practically that nothing is faster than light in vacuum? 19. what is vacuum?

In science and physics what is the standard unit of measure for speed?

What is the force that opposes motion and works against the downward pull? a) friction b) gravity c) weight d) acceleration