me!!! An alpha particle (charge +2e) moves through a potential difference V = -0.310 kV. Its initial kinetic energy is 7.00 1016 J. What is its final kinetic energy? J Consider a square of side p = 2.40 cm with charges of q = +8.50 C at each corner. Find the potential at the center of the square. V Two point charges (+16.50 nC and 16.50 nC) are located 8.00 cm apart. Let U = 0 when all of the charges are separated by infinite distances. What is the potential energy if a third point charge q = 4.20 nC is placed at point b? J An isolated water molecule is modeled as two point charges 0.900e separated by 0.0780 nm. Its rotational inertia is 2.93 1047 kgm2 about the axis shown in the figure below. The molecule is in a uniform electric field of magnitude 466 N/C. If the molecule is initially at rest at = 90.0, what is its angular speed when it reaches = 0, assuming no other forces or torques? rad/s In gel electrophoresis, the mobility of a molecule in a particular gel matrix is defined as = vt/E, where vt is the terminal speed of the molecule and E is the applied electric field strength. In one case, a molecule has mobility 3.51 108 Cm/(Ns) and charge 12e. How long does it take the molecule to move 1.80 cm through the gel if the terminal speed of the molecule is 2.30 105 m/s? min A point charge q1 = +5.00 C is fixed in place at x = 0, and a point charge q2 = 3.70 C is fixed at x = 20.0 cm. At what value of x can we place a point charge q3 = 9.60 C so that the net electric force on q1 due to q2 and q3 is zero? cm Two metal spheres of radius 5.00 cm carry net charges of +1.70 C and +0.300 C. What (approximately) is the magnitude of the electrical repulsion on either sphere when their centers are 1.00 m apart? mN