Related Concept Videos
01:14Mechanisms of Heat Transfer I
Just as interesting as the effects of heat transfer on a system are the methods by which the heat transfer occur. Whenever there is a temperature difference, heat transfer occurs. It may occur rapidly, such as through a cooking pan, or slowly, such as through the walls of a picnic ice box. So many processes involve heat transfer that it is hard to imagine a situation where no heat transfer occurs. Yet, every heat transfer takes place by only three methods: conduction, convection, and radiation.
01:30Work and Heat
Work and heat are fundamental concepts in thermodynamics, denoting the transfer of energy. Work is the energy transferred due to the movement of an object under force, represented as the dot product of the force and displacement vectors. An example can be seen in a gas confined by a frictionless piston. The gas performs work on its surroundings when the piston moves outward, reducing the system's energy.This infinitesimal amount of work (dw) performed by the system against a constant external...
02:46Quantifying Heat
Thermal Energy Microscopically, thermal energy is the kinetic energy associated with the random motion of atoms and molecules. Temperature is a quantitative measure of “hot” or “cold”, which depends on the amount of thermal energy. When the atoms and molecules in an object are moving or vibrating quickly, they have a higher average kinetic energy (KE) (or higher thermal energy), and the object is perceived as “hot”, or it is described as being at a higher temperature. When the atoms and...
02:44Heating and Cooling Curves
When a substance—isolated from its environment—is subjected to heat changes, corresponding changes in temperature and phase of the substance is observed; this is graphically represented by heating and cooling curves.
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
01:24Heat and Free Expansion
The work done by a thermodynamic system depends not only on the initial and final states but also on the intermediate states—that is, on the path. Like work, when heat is added to a thermodynamic system, it undergoes a change of state, and the state attained depends on the path from the initial state to the final state. Consider an ideal gas cylinder fitted with a piston. When the cylinder is heated at a constant temperature, the gas molecules absorb energy and expand slowly in a controlled...
01:14Mechanisms of Heat Transfer
Heat transfer between the human body and its environment occurs through four main mechanisms: conduction, convection, radiation, and evaporation.
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant heat.
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant heat.
You might also read
Related Articles
Articles linked to this work by shared authors, journal, and citation graph.
Sort by
Same author
Tackling malnutrition in older people.
Nursing standard (Royal College of Nursing (Great Britain) : 1987)·2017
Same author
Fresh focus on stroke care.
Nursing standard (Royal College of Nursing (Great Britain) : 1987)·2017
Same author
Never had it so good.
Nursing standard (Royal College of Nursing (Great Britain) : 1987)·2017
Related Experiment Video
Updated: May 31, 2026
06:43
Esophageal Heat Transfer for Patient Temperature Control and Targeted Temperature Management
Published on: November 21, 2017
When the heat is on.
Nursing Standard (Royal College of Nursing (Great Britain) : 1987)
|July 16, 2011
Summary
Summer heat poses serious health risks, particularly for vulnerable populations. Understanding these dangers is crucial for public health and safety during warm weather seasons.
Area of Science:
- Environmental Health
- Public Health
Background:
- Elevated temperatures during summer are generally perceived positively but pose significant health risks.
- Certain demographic groups are disproportionately affected by extreme heat events.
Purpose of the Study:
- To identify vulnerable populations susceptible to heat-related illnesses.
- To understand the life-threatening impacts of high temperatures on specific groups.
Main Methods:
- Literature review on heat-related mortality and morbidity.
- Analysis of demographic data and heat exposure records.
Main Results:
- Specific vulnerable groups experience increased risk of severe health outcomes during heat waves.
- Heat can exacerbate pre-existing health conditions, leading to life-threatening situations.
Conclusions:
- Public health strategies are needed to protect vulnerable individuals from extreme summer heat.
- Targeted interventions can mitigate the adverse health effects of high temperatures.