Problem 5.074 It is well known that, although two materials are at the same temp

Question

Problem 5.074 It is well known that, although two materials are at the same temperature, one may feeler cooler to the touch than the other. Consider thick plates of Copper and Glass, each at an initial temperature of 296 K. Assume your finger to be at an initial temperature of 310 K and to have thermophysical properties of rho = 1000 kg/m^3, c = 4180 /Kg*K, and k = 0.626 W/m*K Assume Specific Heat of Copper at 300: k 385 J/Kg*IK Assume Thermal Conductivity of Glass at 300 K: k 1.4 W/m*K Question 1: What is the rate of heat transfer per unit area 10 seconds after the finger touches copper, in W/? Question 2: What is the contact temperature when the finger touches copper, in K? Question 3: What is the contact temperature when the finger touches glass, in K?

Explanation / Answer

1) we know

rate of heat , Q/t = kA(t2-t1)/d

where , t2 = temperature of finger = 310K

t1 =  temperature of copper = 296K

k = 0.626 W/m*k , t=10sec

Q/A =0.626*(310-296)*10/d

A=1 m2, given in question per unit area

hence, Q = 87.64/d W/m2

according to chegg's policy i can solve only one question at a time, for further solutions please update the question again with respective question number to be solved.

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.