subject
Engineering, 05.05.2020 09:06 Seaqueen3103

1.22

The free convection heat transfer coefficient on a thin hot vertical plate suspended in still air can be determined from observations of the change in plate temperature with time as it cools. Assuming the plate is isothermal and radiation exchange with its surroundings is negligible, evaluate the convection coefficient at the instant of time when the plate temperature is 225°C and the change in plate temperature with times (dT/dt) is -0.022 K/s. The ambient air temperature is 25°C and the plate measures 0.3X0.3 m with a mass of 3.75 kg and a specific heat of 2770 J/kg. K

1.27 Consider the conditions of problem 1.22. However, now the plate is in a vacuum with a surrounding temperature of 25°C. What is the emissivity of the plate?What is the rate at which radiation is emitted by the surface?

ansver
Answers: 2

Another question on Engineering

question
Engineering, 04.07.2019 08:10
Which of the following is an easy way to remember the modified “x” tire rotation? a. nondrive wheels straight, cross the drive wheels b. drive wheels straight, cross the nondrive wheels c. drive wheels crossed, nondrive wheels straight d. drive wheels crossed, nondrive wheels crossed
Answers: 1
question
Engineering, 04.07.2019 18:10
The flow rate of air through a through a pipe is 0.02 m5/s. a pitot static tube is placed in the flow. the radius of the pitot static tube is 1 mm. assuming the flow to be steady and the air to be at 300k, calculate the difference in total and static pressure if the diameter of the pipe is: (a) d 0.1 m d 0.05 m (c) d 0.01 m
Answers: 2
question
Engineering, 04.07.2019 18:10
Courses that are developed by subject matter experts, internal or extemal to the college or university. these programs are marketed by the school (clo2) marks a)-vocational schools b)-vendor training c)-colleges & universities d)-continuing education programs
Answers: 2
question
Engineering, 04.07.2019 18:20
Asolid cylinder is concentric with a straight pipe. the cylinder is 0.5 m long and has an outside diameter of 8 cm. the pipe has an inside diameter of 8.5 cm. the annulus between the cylinder ad the pipe contains stationary oil. the oil has a specific gravity of 0.92 and a kinematic viscosity of 5.57 x 10-4 m2/s. most nearly, what is the force needed to move the cylinder along the pipe at a constant velocity of 1 m/s?
Answers: 3
You know the right answer?
1.22

The free convection heat transfer coefficient on a thin hot vertical plate suspend...
Questions