Question

protons in the cosmic rays strike the earths upper atmosphere at a averaged over the earth 1500 protons/m^2-sec.what is the total charge recieved by the earth from beyond its atmosphere in the form of incident cosmic ray proton ?the earth's radius is 6400 km.
ans is 0.123Cs^-1.

Answer 1

$$\begin{gathered} totalchargereceivedbytheearth=no.ofprotonsperunitarteaperunittime\times chargeoneachproton\times areaoftheearth \\ =1500\times 1.6*{10}^{-19}\times 4\times 3.14\times {\left(6400\times 1000\right)}^2 \\ =0.123C/s \end{gathered}$$