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A small device is used to measure the surface temperature of an object. A thermocouple bead of diameter
If the thermocouple registers a temperature of
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Fundamentals of Heat and Mass Transfer
- Optical properties of Enstatite - Becke line = - Wave plate = - Sign of elongation (Length fast vs. length slow) = - Extinction angle =arrow_forwardA small sphere (emissivity =0.503 radius=r1) is located at the center of a spherical abestos shell ( thickness =1.74 cm, outer radius= r2; thermal conductivity of abestos is 0.090 J/ (sm c degrees) The thickness of the shell is small compared to the inner and outer radii of the shell. The temperature of the small sphere is 695 degrees Celsius while the temperature of the inner surface of the shell is 352 degrees Celsius, both temperatures remaining constant. Assuming that r2/r1 =8.75 and ignoring any air inside the shell, find the temperature in degrees Celsius of the outer surface of the shell.arrow_forwardCalculate the resistive force acting on the disk, with the error level not less than h^4, according to the pressure distribution on a circular disk of 0.5 m diameter held against the air flow, given in the table below.arrow_forward
- Shape factor for a cylinder whose length equals its diameter is 1.5 B. 0.5 1.0 D. 2.0arrow_forwardA helical spring is compressed by a force of 100 N, resulting in a compression length of 20 cm. The spring has a wire diameter of 3 mm and a mean coil diameter of 15 cm. Determine the spring constant (stiffness) of the spring.arrow_forwardA 3-meter high room is heated through a vertical steam pipe. If the bulk temperature of steam in the room was 25 degrees Celsius when the steam in the pipe is 98 degrees Celsius. Determine the minimum dimension of the pipe that could generate a power of 725 Watts if the pipe is (a) square and (b) circular.arrow_forward
- A ship is 35 m long and is designed to move at 11 m/s. Laboratory experiments are carried out in a water tank with a 1 m long model. Find the velocity and the ratio of the resistive forces of the model. (r=1000 kg/m3)arrow_forwardWhat are the types of temperature sensors / devices used in industrial applications? (Give atleast 5 thermocouple sensors).arrow_forward3.A steam at 118°C is flowing inside a diameter of 40 mm, thickness of 10 mm ceramic pipe (k=1.52 W/mK). The pipe is insulated with 25 mm of insulator (k=0.064 W/m K). The convective coefficient for steam inside the pipe is h;=20.7 W/m²K and the convective coefficient for air outside the pipe is h.=0.07W/m²K. The air is at a temperature of 28°C ? (1)Calculate the heat loss per unit length of 1m of pipe (W)? (2)Repeat, using the overall U; based on the inside area A; ?arrow_forward
- between two concentric spherical sheets there is air. The inner spherical sheet has a radius of 10 cm and is filled with ice at 0 ° C, the outer spherical sheet has a radius of 10.05 cm and is at a temperature of 15 ° C. What amount of heat will be transmitted from one sheet to another by conductivity ends in 1/4 hour ?. Considering that the air is pressurized, it is considered to be 15 N / m ^ 2 and at a temperature of 2 ° C. The diameter of the air molecules is taken equal to 3 x 10 ^ -10 m. the molar mass of air is taken equal to 29 g / mol; Boltzman's constant k = 1.38 x 10 ^ -23 J / Karrow_forwardTo find the thermal conductivity of a material, the following experimental setup can be prepared. Two long cylinders that are identical in terms of manufacturing are prepared. One of them is of a known thermal conductivity value kA while the other is for an unknown material kB. Both cylinders are attached to a heat sink of a fixed temperature Tb and they are exposed to a fluid (typically ultra-cooled for accuracy purposes). The temperature measurements are taken along some distance (x1) away from the base. If the first measurements reads 65 C for a distance (x1) of 12 mm while the second material reads 54 C for the same distance. What is the thermal conductivity of the second material (B).Knowns: material A is made of copper. k = 390 W/m.k. Tb = 130 C, Tinf = 12 C.arrow_forwarda) Three blocks A, B, and C and a grooved block D have dimensions a, b, c, and d as follows: a= 1.500 ± 0.001 in b= 2.000 ± 0.003 in c= 3.000 ± 0.004 in d= 6.520 ± 0.010 in Determine the mean gap  ̄w and its tolerance. Determine the mean size of d that will assure that w ≥ 0.010 in. b) A 1-in-diameter rod, 3 ft long, of unknown material is found in a machine shop. A variety of inexpensive nondestructive tests are readily available to help determine the material, as described below with results in bracket: i. Visual inspection. (Dark gray, rough surface finish, moderate scale) ii. Check if it is attracted to a magnet. (Yes) iii. Measure Weight. (7.95lbf) iv. Inexpensive bending deflection test: Clamp one end in a vise, leaving 24 in cantilevered. (5/16in) v. Brinell hardness test. (HB = 200)arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning