Active heat sinks use a fan to draw hot air away from the hardware, making them more compact than passive heat sinks. They are easy to install and remove, but require space for air circulation. Passive heat sinks have a more predictable method of heat transfer but are often too large for standard computer cases. […]
Convective heat transfer occurs through fluid motion and can be natural or forced. Natural convection is caused by varying densities of fluids, while forced convection uses external mechanisms like pumps and fans. Examples include boiling water and the circulatory system in animals. Convective heat transfer is heat transfer by convection, the transfer of heat through […]
Heat energy can be transferred through conduction, convection, and radiation. Objects of different temperatures will try to reach thermal equilibrium, transferring heat from hot to cold. Conduction occurs when molecules transfer heat by bumping into each other, while convection involves the transfer of heat through the movement of fluids. Radiation is the transfer of heat […]
Dry heat sterilization involves heating an item in an oven or heat chamber to kill infectious organisms, even in porous materials. It takes one to two hours and requires preheating to 320-340°F. Non-solid items should be placed in a heat-resistant container. Objects should be allowed to cool before removing from the oven. It is commonly […]
Infrared radiation is felt as heat and can travel through a vacuum. The sun’s infrared heat warms the Earth, and artificial infrared heat is used in industry and therapy. Near infrared is used for data transmission, while medium and far infrared waves are felt as heat. Infrared refers to the wavelengths of the electromagnetic spectrum […]
Urban areas have higher temperatures than rural areas due to materials such as concrete and asphalt absorbing sunlight and retaining heat. This causes health risks and financial costs, but planting trees and using lighter colored surfaces can reduce the heat island effect. Los Angeles is proposing a program to repaint streets, plant trees, and renovate […]
The heat transfer coefficient measures how easily heat energy moves between materials, with factors such as temperature and convection affecting the transfer. It is important in industries such as cookware, machinery, and insulation. The coefficient is calculated using the amount of heat transferred per unit area and the temperature difference between surfaces. Understanding overall coefficients […]
Heat sources can be natural or man-made and include geothermal heat, solar energy, and nuclear heat. Natural sources have advantages such as being long-lived, but can be inconsistent. Man-made sources include nuclear heat, which generates electricity through the decay of radioactive elements. A heat source is any area, object or mechanism that creates heat. Heat […]
Thermal heat energy is a form of energy that increases the movement of atoms in a substance, causing effects such as expansion and increased reactivity. Heat causes atoms to vibrate, move faster, and collide, increasing the rate of chemical reactions. Energy transfer occurs due to temperature differences between two systems, and within a closed system, […]
Heat rash, also known as milaria, is a skin condition caused by excessive heat that clogs sweat glands, resulting in a reddish, pimple-like rash. It can be prevented by staying clean and cool, and treated with astringents and cooling compresses. Infants, young children, runners, and people in hot, humid climates are particularly susceptible. Recurring or […]
Heat of solution is the enthalpy change that occurs when a solute dissolves in a solvent. The process involves breaking chemical interactions, requiring energy consumption, and forming new interactions, releasing energy. The total heat of solution is the sum of each enthalpy change and can be endothermic or exothermic. Temperature changes can also be used […]
Heat fatigue is a warning sign of heat-related illness and can lead to heat stroke. Symptoms include sweating, rash, confusion, and sluggishness. Proper precautions, such as breaks and hydration, can prevent serious health complications. Treatment includes rehydration and monitoring in a hospital. Heat fatigue is one of several warning signs of heat-related stress and illness. […]
“Dead heat” is an idiom for a tie in any race, originating from horse racing where the first horse to win a certain number of heats is declared the winner. It can also refer to close competition in other fields and has been used as a title in books and movies. The phrase “dead heat” […]
