2. The average person has 1.4 m2 of skin at a skin temperature of roughly 305...
Radiation of Energy The rate of heat transfer by emitted radiation is determined by the Stefan-Boltzmann law of radiation: = aeAT4 where o 5.67x10-8 J/s - m2 K is the Stefan-Boltzmann constant, A is the surface area of the object, and T is its absolute temperature in kelvin. The symbol e stands for the emissivity of the object, which is a measure of how well it radiates An ideal jet-black (or black body) radiator has e 1,whereas a perfect reflector has...
Calculate the rate of energy loss due to thermal radiation from an unclothed person if the average skin temperature is 37 °C and the room temperature is 20 °C. You may sume a total surface area of 1.5 m and a skin emissivity value of 0.9. How much energy (from food) must be consumed per day to compensate for this loss? If the person is surrounded by a layer of insulation of thickness 1.0 cm with a thermal conductivity of...
The rate of heat transfer by emitted radiation is determined by the Stefan-Boltzmann law of radiation = ceAT4 t where a 5.67x108 J/(s m2. K4) is the Stefan-Boltzmann constant, A is the surface area of the object, and T is its absolute temperature in kelvin. The symbol e stands for the emissivity of the object, which is a measure of how well it radiates. An ideal jet-black (or black body) radiator has e 1, whereas a perfect reflector has e...
Electromagnetic Wave Questions 2. Our sun has a power output of roughly 3.87 1026 watts (W). This energy is transmitted essentially uniformly in all directions. By the time this radiation reaches the Earth, which has an average distance from the sun of 1.50 x 10" m, what is the intensity? (Recall that intensity is defined to be power per unit area). 3. The energy from the sun is primarily in the infrared and visual wavelengths. The following table gives the...
Al is metal, silvery in colour, with a resistivity of 2.65 μΩ.cm at room temperature. it has the so-called face centred cubic (FCC) structure, in which the fractional coordinates of the atoms within the (conventional cubic, side length of a 4.046 A) unit cell are: (0,0,0), (12%,0), (12,0,%), (0,%,%) The intermetallic compound AbAu is bright purple in colour, has a melting point of 1060°C, is rather brittle, and has a resistivity of p-8 u2.cm.1 the repeating unit is also cubic...
e. 18 Test Your Knowledge MULTIPLE CHOICE: Choose the one best answer. 1. Each element has its own characteristic atom in which a. the atomic mass is constant. b. the atomic number is constant. c. the mass number is constant. d. Two of the above are correct. e. All of the above are correct. 2. Which of the following is not a trace element in the human body? a. iodine b. zinc c. iron d. calcium e. fluorine 3. A...
Need answers. thank you VOCABULARY BUILDER Misspelled Words Find the words below that are misspelled; circle them, and then correctly spell them in the spaces provided. Then fill in the blanks below with the correct vocabulary terms from the following list. amino acids digestion clectrolytes nutrients antioxident nutrition basal metabolic rate extracellulare oxydation calories fat-soluble presearvatives catalist glycogen processed foods cellulose homeostasis saturated fats major mineral coenzyeme trace minerals diaretics metabolism water-soluable 1. Artificial flavors, colors, and commonly added to...