When an object with an electric charge of −0.050 mC is 9.0 m away from an object with an electric charge of −0.080 mC, the electric potential energy is measured to be 3.994 J.   Calculate the electric potential energy of this system when the objects are 18. m apart. Be sure your answer has a unit symbol and round your answer to 2 significant digits.

What is the electric potential at the dot in the figure? The charge on Q1 is 4.00 nC, the charge on Q2 is 5.00 nC and the charge on Q3 is 3.00 nC. The distance between charge Q1 and charge Q2 is 7.00 cm. The distance between Q2 and Q3 is 2.00 cm. 2.80×103 V 2.42×103 V 2.18×103 V 1.00×103 V

The work done by an electricforce in moving a charge from point A to point B is 2.51x 103 J. The electric potential difference between the two points is VA- VB = 55.9 V. What is the charge? Number Units

Consider two points in an electric field. The potential at point 1, V1, is 48 V. The potential at point 2, V2, is 153 V. An electron at rest at point 1 is accelerated by the electric field to point 2.    Part (a)  Write an equation for the change of electric potential energy ΔU of the electron in terms of the symbols given.   Part (b)  Find the numerical value of the change of the electric potential energy in electron volts (eV).  ΔU =   Part (c)  Express v2, the speed of the electron at point 2, in terms of ΔU, and the mass of the electron me.  v2 =     Part (d)  Find the numerical value of v2 in m/s.  v2 =

A potential difference exists between the inner and outer surfaces of the membrane of a cell. The inner surface is negative relative to the outer surface. If 1.35 × 10-20 J of work is required to eject a positive sodium ion (Na+) from the interior of the cell, what is the magnitude of the potential difference between the inner and outer surfaces of the cell? magnitude of the potential difference:

As stated in the pic

Two protons are released from rest, one from location 1 and another from location 2. When these two protons reach location 3, the first proton has a speed that is 2 times the speed of the second proton. If the electric potentials at locations 1 and 2 are 231 V and 115 V, respectively, what is the electric potential at location 3? V

A solid aluminum sphere with radius a has an explicitly negative charge,−q. Concentric with the aluminum sphere is a copper spherical shell with inner radius b, outer radius c, and an explicitly positive charge, +Q. Assume that the magnitude of the positive charge on the copper shell is greater than the magnitude of the negative charge on the aluminum sphere, and take the electric potential at infinity as zero. Enter an expression for the electric potential, V, that is valid for a