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. Going for a swim in a cold pool, or sticking your hand out of a car window while driving are both examples of convection. Given the surface temperature of

your hand is about 95 °F: A. determine the convective heat flux (q") for placing your hand outside on a cold winter day driving at 40 mph with T= 18 °F and a convective heat transfer coefficient of 37.5 Btu/h-ft2-°E. B. what is the convective heat flux if your place your hand in a stream of cold water moving at 5 mph at 70 °F with a convective heat transfer coefficient of 277 Btu/h-ft²-F? C. Which of the above situations would feel colder to you? D. How do these numbers compare to the normal heat fluxes from the body to room temperature (still) air of around 10 Btu/h-ft2? Explain why there is a difference E. What would happen to q" if the velocities of either the air in (A) or the water in (B) were increased (Give a QUALITATIVE ANSWER- go up, stay the same, decrease)? Which term in Newton's law of cooling must be a function of velocity?

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