# Danger? I laugh at danger!

One day, I was out bicycling when a thunderstorm cropped up. While frantically pedaling home at a speed of $$10~\mbox{km/hr}$$, a wind blew a power line down and it brushed against the inside of my front wheel, putting a positive $$1~\mbox{C}$$ charge on the wheel. I kept pedaling. If my bicycle wheels have radius $$0.3~\mbox{m}$$, what is the magnitude of the generated magnetic field in Teslas that I on my bike would measure at a distance of $$0.1~\mbox{m}$$ perpendicular from the center of my front wheel?

Details and assumptions

• Treat the wheels as thin conducting hoops.
• You may assume the charge has spread out over the wheel but not left it yet.
• My bike wheel was not slipping on the ground as I traveled.
• The vacuum permeability is $$\mu_0=4\pi \times 10^{-7}~\mbox{H/m}$$.
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