Correct Answer:- Option-D

Questiondo:-A metallic ball (p= 2700 ka/yn3 and Cp = 0.9 KJ/kg.°C) of diameter 7.5 cm is allowed to cool in air at 25°C. When the temperature of the ball is 125°C, itis found to cool
at the rate of 4°C/min. If thermal gradients inside the ball are neglected, the heat transfer coefficient (in W772 .°C) is.

۸2034
‏2د میھ‎
6
24
Correct Answer:- Option-8
Question4l:-Select the corresponding finite-difference equation for the node (m, n) as shown in the below figure.

27 ‏مر‎ + Tmnal +P mnti-4T'mn =0

Tm-in+T mn-l + 27 mnt - 47 ‏مو‎

‎mani +P mnt 4T mn =0‏ 27+ سم

‎
‎

‎‘maint Taal +Tmnti~ Tmn =0
Correct Answer:- Option A,

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1007० pistes given belo

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‎Hike thal conductivity oar at fl temperate is k= 0.0202 Win, ten, te convection hea (സഗ 0

‎

‎20°C over a plate surface maintained at a constant temperature of 7", = 160°C, the dimensionless temperature profile within the air

‎

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‎8:8

‎

‎58
‎Correct Answer:- Option-B

‎‘Question43:-Water flows through a 20 mm diameter at a rate of 0.01 kg/s entering at 10°C. The tube is wrapped from outside by an electric heating element that produces a uniform
heat flux of 15 kW/y7,2 . If the exit temperatute of the water is 40°C, estimate the heat transfer coefficient (in W/y,2 -K). The thermal conductivity of water is 0.608 W/m.K.

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‎83.66
‎೦29.33
‎02325
‎Correct Answer:-Question Cancelled

‎Questiond4:-The spectral distribution of surface irradiation is given below, then what is the total irradiation (in W/ 72) ?

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‎

‎222000.

‎80

‎00

‎

‎:-25000
‎Correct Answer:- Option-8

‎Questiona5:-In film type condensation over a vertical tube, the local heat transfer coefficient is.
Asinversely proportional to the local film thickness
B:-Directly proportional to the local film thickness

‎CEqual to the local film thickness