Question

Statement 1: When heat transfer takes between a solid surface and a fluid, an insulating film layer is formed. More is the agitation; more is the thickness of the film.

Statement 2: Within the film, the temperature varies from the wall to the temperature of the bulk.

(a) True, False

(b) True, True

(c) False, False

(d) False, True

I have been asked this question by my school principal while I was bunking the class.

My doubt stems from Unit Operations in chapter Heat Transfer by Conduction, Convection and Radiation of Food Engineering

Answer 1

Right option is (d) False, True

To elaborate: When heat transfer takes between a solid surface and a fluid, an insulating film layer is formed. More is the agitation; lesser is the thickness of the film. Within the film, the temperature varies from the wall to the temperature of the bulk.