The amount of radiation energy emitted from a surface at a g
     The amount of radiation energy emitted from a surface at a given wavelength depends on:  The material of the body  The condition of its surface  The surface temperature  All of the above  Fouling of heat exchangers:  Decrease with temperature and decreasing with velocity  Decrease with temperature and increase with velocity  Increase with temperature and increase with velocity  Increase with temperature and decreasing with velocity  Diffuse emitter is a:  Gray body  Black body  White body  Gray and blackbody  Emissivity of Gray body in comparison to blackbody is  Higher  Lower  Equal  Slightly higher  Wave length range of thermal radiation:  1/10 to 1/100 mu m  1/10 to 1/1000 mu m  1/10 to 100 mu m  1/10 to 1000 mu m  Square pattern tube layouts in heat exchangers are employed where  Laminar flow is experienced  Turbulent flow is experienced  High fouling is experienced  Low fouling is experienced 
  
  Solution
1.c..only temperature
2.c.increase with temp decrease with velocity
3.b.black body is diffuse emitter
4.lower..b
5.0.1um to 100um..c
6.c.where high fouling is experienced

