MCQs
Total Questions : 75
| Page 8 of 8 pages
Answer: Option C. -> Aluminum fin
Answer: (c).Aluminum fin
Answer: (c).Aluminum fin
Answer: Option C. -> 1, 2 and 3
Answer: (c).1, 2 and 3
Answer: (c).1, 2 and 3
Question 73. A heating unit is made in the form of a vertical tube of 50 mm outside diameter and 1.2 m height. The tube is fitted with 20 steel fins of rectangular section with height 40 mm and thickness 2.5 mm. The temperature at the base of fin is 75 degree Celsius, the surrounding air temperature is 20 degree Celsius and the heat transfer coefficient between the fin as well as the tube surface and the surrounding air is 9.5 W/m² K. If thermal conductivity of the fin material is 55 W/m K, find the amount of heat transferred from the tube with fin
Answer: Option B. -> 1004.84 W
Answer: (b).1004.84 W
Answer: (b).1004.84 W
Question 74. Two long rods A and B of the same diameter have thermal conductivities k and 4k and have one of their end inserted into a furnace at 400 K. At 9.5 m away section from the furnace, the temperature of rod B is120 degree Celsius. So find out at what end from the furnace end, the same temperature would be reached in the rod A?
Answer: Option A. -> 0.25 m
Answer: (a).0.25 m
Answer: (a).0.25 m
Answer: Option A. -> Greater than 5
Answer: (a).Greater than 5
Answer: (a).Greater than 5