question_answer

A radioactive source, in the form of a metallic sphere of radius \[{{10}^{-2}}m\] emits (\[\beta \] - particles at the rate of \[5\times {{10}^{10}}\] particles per second. The source is electrically insulated. How long (in second) will it take for its potential to be raised by 2V, assuming that 40% of the emitted \[\beta \]- particles escapes the sources?

Answer:

\[\left( 6.94\times {{10}^{-4}} \right)\]