thermal hazard
(noun)
an electrical hazard caused by overheating (e.g., in a resistive element)
Examples of thermal hazard in the following topics:
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Humans and Electric Hazards
- The hazards from electricity can be categorized into thermal and shock hazards.
- There are two known categories of electrical hazards: thermal hazards and shock hazards.
- A thermal hazard is when excessive electric power causes undesired thermal effects, such as starting a fire in the wall of a house.
- A thermal hazard can be created even when a short circuit is not present if the wires in a circuit are overloaded with too much current.
- Thermal hazards can cause moderate to severe burns to those who come in contact with the affected appliance or circuit.
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Safety Precautions in the Household
- Electrical safety systems and devices are designed and widely used to reduce the risks of thermal and shock hazards.
- Electricity has two hazards.
- A thermal hazard occurs in cases of electrical overheating.
- A shock hazard occurs when an electric current passes through a person.
- There are many systems and devices that prevent electrical hazards .
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Deinococcus and Thermus
- The Deinococcus-Thermus are a small group of bacteria composed of cocci highly resistant to environmental hazards.
- The Deinococcus-Thermus are a small group of bacteria composed of cocci that are highly-resistant to environmental hazards.
- The Thermales include several genera resistant to heat (Marinithermus, Meiothermus, Oceanithermus, Thermus, Vulcanithermus).
- This is the one genus of three of the Deinococcales group from the Deinococcus-Thermus phylum, and is highly-resistant to environmental hazards.
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Asymmetric Information: Adverse Selection and Moral Hazard
- In addition to adverse selection, moral hazards are also a result of asymmetric information.
- A moral hazard can occur when the actions of one party may change to the detriment of another after a financial transaction.
- For example, moral hazards occur in employment relationships involving employees and management.
- A lack of equal information causes economic imbalances that result in adverse selection and moral hazards.
- An insured driver getting into a car accident is an example of a moral hazard.
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Thermal Stresses
- Solids also undergo thermal expansion.
- What are the basic properties of thermal expansion?
- What is the underlying cause of thermal expansion?
- Thermal stress is created by thermal expansion or contraction.
- Another example of thermal stress is found in the mouth.
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The Zeroth Law of Thermodynamics
- The Zeroth Law of Thermodynamics states that systems in thermal equilibrium are at the same temperature.
- Systems are in thermal equilibrium if they do not transfer heat, even though they are in a position to do so, based on other factors.
- If A and C are in thermal equilibrium, and A and B are in thermal equilibrium, then B and C are in thermal equilibrium.
- Temperature is the quantity that is always the same for all systems in thermal equilibrium with one another.
- The double arrow represents thermal equilibrium between systems.
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A Review of the Zeroth Law
- The Zeroth Law of Thermodynamics states: If two systems, A and B, are in thermal equilibrium with each other, and B is in thermal equilibrium with a third system, C, then A is also in thermal equilibrium with C.
- Two systems are in thermal equilibrium if they could transfer heat between each other, but don't.
- Indeed, experiments have shown that if two systems, A and B, are in thermal equilibrium with each other, and B is in thermal equilibrium with a third system C, then A is also in thermal equilibrium with C.
- The answer lies in the fact that any two systems placed in thermal contact (meaning heat transfer can occur between them) will reach the same temperature.
- The objects are then in thermal equilibrium, and no further changes will occur.
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Thermal Radiation
- $\displaystyle \text{Another Kirchoff's Law: }S_\nu = B_\nu(T) \text{ for a thermal emitter}$
- Because $I_\nu=B_\nu(T)$ outside of the thermal emitting material and $S_\nu=B_\nu(T)$ within the material, we find that $I_\nu=B_\nu(T)$ through out the enclosure.
- If we remove the thermal emitter from the blackbody enclosure we can see the difference between thermal radiation and blackbody radiation.
- A thermal emitter has $S_\nu = B_\nu(T)$,$B_\nu(T)$ so the radiation field approaches $B_\nu(T)$ (blackbody radiation) only at large optical depth.
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Thermal Pollution
- Thermal pollution is the degradation of water quality by any process that changes ambient water temperature.
- Thermal pollution is the degradation of water quality by any process that changes ambient water temperature.
- Some fish species will avoid stream segments or coastal areas adjacent to a thermal discharge.
- Some may assume that by cooling the heated water, we can possibly fix the issue of thermal pollution.
- Identify factors that lead to thermal pollution and its ecological effects
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Electrocyclic Reactions
- In the first case, trans,cis,trans-2,4,6-octatriene undergoes thermal ring closure to cis-5,6-dimethyl-1,3-cyclohexadiene.
- The second diagram below shows two examples of thermal electrocyclic opening of cyclobutenes to conjugated butadienes.
- Photochemical ring closure can be effected, but the stereospecificity is opposite to that of thermal ring opening.