In sci.engr.lighting JS wrote:
Table 4H3B gives the volt drop of the cable in mV/A/m. You
should allow for a maximum of 2% drop in voltage at the far end
of your flex.

I'm not sure *why* you would want to know the resistance per se,
but you can work out the resistance from these figures.

Hi Rumble

I was hoping to measure the resistence across the live/neutral pins
of the mains plug and then deduct the resistence of the main lead
(which is approx 10m of 1.0 mm^2).

From the result I was looking to know what the cold bulb resistence
is and from that infer the wattage.

The idea is to save opening up the housing and taking the bulb out to
measure the resistence.

Unfortunatrely, the cold resistnace of a bulb has very little to do
with its hot resistance.
Design differences may even mean one with lower wattage has a lower
cold resistance.
Does your multimeter happen to have an AC current measurement?