At the maximum power output of a solar panel, the voltage and current are $18 \mathrm{~V}$ and $5.56 \mathrm{~A},$ respectively. If the open circuit voltage and short circuit current of the same solar panel are $21.6 \mathrm{~V}$ and $6.11 \mathrm{~A},$ respectively, the fill factor of the panel (round off to 2 decimal places) is___________________
At the maximum power output of a solar panel, the voltage and current are $18 \mathrm{~V}$ and $5.56 \mathrm{~A},$ respectively. If the open circuit voltage and short circuit current of the same solar panel are $21.6 \mathrm{~V}$ and $6.11 \mathrm{~A},$ respectively, the fill factor of the panel (round off to 2 decimal places) is___________________