91Ó°ÊÓ

(I) How much work does the electric field do in moving a -7.7\(\mu\)C charge from ground to a point whose potential is \(+\)65 V higher?

(I) How much work does the electric field do in moving a proton from a point at a potential \(+\)125V of to a point at \(-\)45 V? Express your answer both in joules and electron volts.

(I) How much kinetic energy will an electron gain (in joules and eV) if it accelerates through a potential difference of 18,500 V?

(I) An electron acquires 6.45 \(\times\) 10\(^{-16}\) of kinetic energy when it is accelerated by an electric field from plate A to plate B. What is the potential difference between the plates, and which plate is at the higher potential?

(I) How strong is the electric field between two parallel plates 6.8 mm apart if the potential difference between them is 220 V?

(I) An electric field of 525 V/m is desired between two parallel plates 11.0 mm apart. How large a voltage should be applied?

(I) The electric field between two parallel plates connected to a 45-V battery is 1900 V/m. How far apart are the plates?

(I) What potential difference is needed to give a helium nucleus \((Q = 2e)\) 85.0 keV of kinetic energy?

(II) Two parallel plates, connected to a 45-V power supply, are separated by an air gap. How small can the gap be if the air is not to become conducting by exceeding its breakdown value of \(E = 3 \times 10^{6}\)V/m?

(II) The work done by an external force to move a -6.50\(\mu\)C charge from point A to point B is 15.0 \(\times\) 10\(^{-4}\)J. If the charge was started from rest and had 4.82 \(\times\) 10\(^{-4}\)J of kinetic energy when it reached point B, what must be the potential difference between A and B?