Incandescent bulbs: 10 lumens per watt
Halogens: 13 lumens per watt
CFLs: 50 lumens per watt
A useful bulb to light a small room is 600 lumens, so that would need a 60-watt incandescent, or a 45-watt halogen, or a 12-watt CFL energy-saving bulb.
The best CFL bulbs are the spiral ones.
Lumens and watts measure different things, so they cannot be "equal" or converted unless you make some big assumptions. Lumens refers to the amount of light in the visible spectrum within a viewing angle; watts refers to the amount of power.
For instance, an incandescent bulb of 100 Watts might emit about 1500 lumens (360 degrees), but a compact fluorescent (CFL) bulb might only need 22 watts to generate the same amount of light and an LED bulb might give 1500 lumens with only 15 watts or so (typically in a much narrower viewing angle).
Another Answer
A lumen measures the output power (i.e. its luminous flux) of a lamp in the photometric system. The watt measures the output power of a lamp in the radiometric system (it is also used to measure a lamp's power input).
In the radiometric system, the watt measures the rate at which emits electromagnetic energy across all frequencies, whereas in the the photometric system, the lumen measures the rate at which electromagnetic energy is emitted as visible light, corrected for the sensitivity of the human eye.
The relationship between a lamp's input power (in watts) and its output luminous flux is termed the 'efficacy' (not 'efficiency'!) 's the light source, and is expressed in lumens per watt. Efficacy depends upon the type of light source -e.g. an incandescent lamp has an efficacy of between 5-15 lumens per watt.
6000
That will vary on the manufacture and quality of the bulb. There is no set amount of lumens for a 40 watt halogen or any kind of bulb for that matter. To find out the lumen output you need to look at the box it came in as it should be stated. If you don't have the box it may be tricky to find out. You will have to see if you can find the manufacture somewhere on the bulb then google it and check the specs. It's probably safe to say its going to be around 500 lumens on average.
The bulb will have an efficacy of 17-20Lm per watt, so in total 500W = 8,500-10000 lumens. However, the bulbs light output is non directional, so a lot of the spilled light is in directions that you don't want it to go, so 50-70% of the figure can be used when specing up an LED variant.
The watt is a measurement of work done by an object at constant velocity and under constant force. 1 watt, therefore, is equal to 1 Joule per second.
Luminous efficacy is a figure of merit for light sources. It is the ratio of luminous flux (in lumens) to power (usually measured in watts). As most commonly used, it is the ratio of luminous flux emitted from a light source to the electric power consumed by the source, and thus describes how well the source provides visible light from a given amount of electricity.This is also referred to as luminous efficacy of a source.
A 1,000 watt is 15,000 lumens. A 100 watt bulb is 1,500 lumens.
Approximately 15 lumens per watt for halogen, so 300 lumens.
2300lm Comment I think you mean lumens, not lumen's. No that answer is wrong Watts (energy usage) / Lumens (light output) 25 is equal to 200 35 is equal to 325 40 is equal to 450 60 is equal to 800 75 is equal to 1100 100 is equal to 1600 125 is equal to 2000 150 is equal to 2600 36 watts would be about 350 Lumens
a 42 watt cfl give off 2800 lumens
The maximum lumens that a 1-watt LED flashlight can have now is 160.
1800lumens per watt
around 21,000 average 100 watt bulb is around 1400 lumens. That's 14 lumens per watt. 14X1,500 = 21,000
From 20,000 to 23,000 lumens depending on the brand.Average figures:Incandescent: 10 lumens per wattHalogen 13 lumens per wattCFL (low-energy) 50 lumens per watt
A 150-watt light bulb uses energy at the rate of 150 watts, when it's turned on.
Incandescent bulbs give about 10 lumens of light per watt of electric power Halogens give about 13 lumens per watt CFLs give about 50 lumens per watt So it depends on the type of bulb.
It's about 600 lumens. The same brightness comes from a 12 Watt compact fluorescent light (CFL).
The main types are: Incandescent 10 lumens per watt Halogen 13 lumens per watt Fluorescent 40-50 lumens per watt LED 40-60 lumens per watt Lumens measures the brightness, watts measures the electric power used.