Which would result in a judge who is sitting beside the testing ground observing the tennis ball having a speed of 7 m/s?

What is the final velocity of the initial velocity of 25 and -50?

How to tell if a molecule is polar or nonpolar with electronegativity

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e