What do all isotopes of an element have in common

Point charges q1=+2.00μc and q2=−2.00μc are placed at adjacent corners of a square for which the length of each side is 1.50 cm . point a is at the center of the square, and point b is at the empty corner closest to q2. take the electric potential to be zero at a distance far from both charges. part a what is the electric potential at point a due to q1 and q2? express your answer with the appropriate units.

Ball bearings are made by letting spherical drops of molten metal fall inside a talll tower-called a shot tower- and solidify as they fall. a-if a bearing needs 4.0 s to solidify enough for impact, how high must the tower be? b- what is the bearing's impact velocity?

Which statements best describe the work of marie and pierre curie? check all that apply. they discovered radioactivity. they came up with the term “radioactivity.” they conducted experiments with uranium-containing minerals and pure uranium. they conducted experiments with uranium-containing minerals and photographic plates. they discovered two new radioactive elements.