Question

At what pressure did discharge occur between the two electrodes when an electric field was applied to the gas in the discharge tube?

Options

• About 10 mm of mercury column

• About 1 mm of mercury column

• About 0.1 mm of mercury column

• About 0.001 mm of mercury column

Answer 1

At sufficiently low pressure, about 0.001 mm of mercury column, an applied electric field caused discharge between the two electrodes.