Easy EPE problem

I keep getting 4.259 e-18 and don't know what I'm doing wrong An electron and a proton are initially very far apart (effectively an infinite distance apart). They are then brought together to form a hydrogen atom, in which the electron orbits the proton at an average distance of 5.41 x 10-11m. What is EPEfinal - EPEinitial, which is the change in the electric potential energy?

hat isthe maximumemf generated when the coil totatesrnatingcurrent circuits

A 2-cm by 1.5-cm rectagler coil has 300 turnsa and rotates in a magnetic field of 4000 G. a)What is the maximum emf generated when the ciol rotates a maximum 60 HZ? B)What must its frequency be to generate a maximum emf of110 V? please explain details, thanks

Alternating currents

An emf of10 Vmaximum and frequency 20 Hz is appliedto to a 20uF capacitor. Find (a) 1 sub max and (b) I sub rms.

alternating currents

A coil has a dc resistance of of the coio80 omega and animpendence 20 omegs at a frequency od 1 kHz. Neglect the wring capacitance of the coil at this freqqency. What is the inductance of the coil? pls write details of steps

Alternating currents

Show that the average power dissipated in the resistor of the high-pass filter of problem 48? p sub ave = V^2 sub peak ( (wRC)^2) __________________________________ 2R (1+(wRC)^2)