A point charge (q, mass m) is released from rest at a distance d from a grouned infinite conducting plane. How long does it take to hit the plane?(adsbygoogle = window.adsbygoogle || []).push({});

Answer pi*(d/q)*sqrt(2pi*eps m d)

This problem seemed easy to me at very, but it leads to a second order nonlinear equation

[tex]m\frac{d^2 z}{dt^2} = \frac{q^2}{16 \pi \epsilon_0 z^2}[/tex].

I tried using energy considerations to write v as v(z), I then solved for z as z(v), and integrated the above equation for v(t), putting in the limits 0 and infinity. This did not give the correct answer, although it appeared to be close. Any suggestions?

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# Homework Help: E&M Griffiths 3.34

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