An external circuit provides a path for the electrons to return to the p-type material, producing an electric current along the way that continues as long as light strikes the solar cell.

此时接上一条外线电路，电子便通过线路流动到p层。只要光束持续地撞击太阳能电池，就会有持续的电流。

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These use an electric current to heat and ablate a material, producing a charged gas that can then be accelerated in one direction in a magnetic field to push the cubesat in the other direction.

BBC: Strand-1 'phone-sat' ready for orbit