Two large parallel grey plates with a small gap exchange radiation at a rate of 1000 W/m2, when their emissivities are 0.5 each. One plate is cooled such that its emissivity becomes 0.25. Find the new rate of heat transfer if the temperature difference remains the same.
1
850 W/m2
2
550 W/m2
3
600 W/m2
4
1000 W/m2