The light output of a fluorescent tube is typically measured in lumens (lm). However, the light output of a fluorescent tube is not directly determined by its wattage. Instead, it depends on various factors, including the efficiency of the tube and the specific design characteristics.
On average, a 40-watt fluorescent tube can produce around 3000 to 3500 lumens of light output. However, it's important to note that different types of fluorescent tubes can have varying efficiencies and light outputs. Additionally, factors such as the age of the tube, the quality of the ballast, and the temperature can also affect the light output.
For more accurate information about the light output of a specific fluorescent tube, it is recommended to refer to the product specifications or consult the manufacturer's documentation.