The operating temperature of a tungesten filament in an indandescent lamp is `2000 K ` and its emissivity is `0.3`.
Find the surface area of the filament of a `25` watt lamp. Stefan's constant ` sigma = 5.67xx10^(-8) Wm^(-2)K^(-4)`

The operating temperature of a tungsten filament in an incandescent lamp is 2000 K and it's emissivity is 0.3 . Find the surface area of the filament of a 25 watt lamp. Stefan's constant sigma = 5.67 × 10^-8 W m^-2 K^-4

A 100 watt filament loses all its power by radiation when it is heated to a temperature of 2500 K. If the diameter of the filament is 0.2 mm and the surface emissivity of the filament is 0.5, find the length of the filament. (Stefan's constant sigma = 5.67 xx10^-8 W/m^2k^4 )

How much energy in radiated per minute from the filament of an incandescent lamp at 3000 K, if the surface area is 10^(-4)m^(2) and its emissivity is 0.4 ? Stefan's constant sigma = 5.67 xx 10^(-8) Wm^(-2)K^(-4) .

The temperature of the tungsten filament of a 60-watt electric bulb is T=2000K . Find the surface of the filament. The emmissivith of the surface is e=0.30 .

What will be the surface area of a filament of 200 W incandescent lamp at 2000 K. sigma = 5.67 xx 10^(-8) Wm^(-2) K^(-4) and emissivity e = 0.3?

How much energy is radiated per minute from the filament of an incandescent lamp at 3000 K , if the surface area is 10^-4 m^2 and it's emissivity is 0.4 ? Stefan's constant sigma = 5.67 × 10^-8 W m^-2 K^-4

A 500W lamp loses all of its energy by emission of radiation from the surface. If the area of the surface of the filament is 2.0cm^(2) and its emissivity is 0.5, estimate the temperature of its filameiit. Given that Stefan constant, sigma =5.7xx10^(-8)W//m^(2)K^(4). Neglect radiation receivedby lamp from surrounding.

The operating temperature of an in candescent bulb (with tungsten filament) of power 60 W is 3000 K. If the surface area of the filament be 25 mm^2 , find its emissivity e.

The operating temperature of an in candescent bulb (with tungsten filament) of power 60 W is 3000 K. If the surface area of the filament be 25 mm^2 , find its emissivity e.

The temperature of the filaments of a 100W electric lamp is 2727^@C . The emissivity of the surface of the filament is 0.086 and its radius is 0.5 mm. Find the length of the filament. sigma = 5.7 xx 10^-8 S.I. units.