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Does heat transfer require no direct contact between the warmer and cooler substances?
Conductive heat transfer requires direct contact between warmer and cooler substances. However, two types of heat transfer require no direct contact between the warmer and cooler surfaces: convective heat transfer and radiative heat transfer.
In convective heat transfer, the warmer substance heats some intermediate substance - a gas like air or a liquid like water - which then moves either due to natural convection due to density differences or by forced convection driven by a pump or fan. The warmed fluid then imparts some of the energy it picked up from the warmer substance to heat up the cooler substance. In truth, this still relies on conduction to heat the fluid between the two and for the fluid to then heat the cooler substance, but there is clearly no direct contact between the heat source and the heat sink.
In radiative heat transfer, the energy is transferred between the two substances without any intermediate fluid. If it didn't work, the sun would be unable to warm the earth. The transfer occurs via electromagnetic radiation from the hotter substance to the cooler one. In truth, the cooler substance is also radiating back to the warmer one, but it receives much more energy from the warmer one than it is able to send back. The rate of radiation is proportional to the fourth power of the absolute temperature of the substance, so the net heat transfer between two substances is expressed by the formula:
q = ε σ (Th4 - Tc4) Ac
where q is rate of heat transferred, ε is the emissivity of the heat source, σ is the Stefan-Boltzmann constant, A is the surface area, and Th and Tc are the absolute temperature of the hot and cold substances respectively.
What else can I help you with?
What is the method of transfer that does not require contact?
One method of transfer that does not require contact is through radiation. Radiation is the transfer of energy in the form of electromagnetic waves, such as light or heat, without the need for physical contact between objects.
Does conduction require direct contact?
Yes, conduction involves the transfer of heat through direct contact between objects or substances. This transfer occurs as vibrating molecules pass their kinetic energy to neighboring molecules. Heat is transferred from the warmer to the cooler object until thermal equilibrium is reached.
What are the differences between conduction convection and radiation?
Conduction-happens when heat moves from one object to another through direct contact Radiation-happens when energy ,such as heat, moves in waves between one object and another Convection-happens when matter carries heat from one place to another
Does conduction require direct contact between objects objects have to be touching?
Yes, conduction does require direct contact between objects for heat transfer to occur. This is because heat is transferred through the collision of particles in direct contact with each other. If there is no direct contact, conduction cannot take place.
Is Convection is the flow of heat energy direct contact between molecules?
Convection is the transfer of heat through the movement of fluids or gases. It does not require direct contact between molecules, as the heat energy is carried by the movement of the fluid itself.
What is the method of transfer that does not require contact?
One method of transfer that does not require contact is through radiation. Radiation is the transfer of energy in the form of electromagnetic waves, such as light or heat, without the need for physical contact between objects.
Does conduction require direct contact?
Yes, conduction involves the transfer of heat through direct contact between objects or substances. This transfer occurs as vibrating molecules pass their kinetic energy to neighboring molecules. Heat is transferred from the warmer to the cooler object until thermal equilibrium is reached.
What are the differences between conduction convection and radiation?
Conduction-happens when heat moves from one object to another through direct contact Radiation-happens when energy ,such as heat, moves in waves between one object and another Convection-happens when matter carries heat from one place to another
Does conduction require direct contact between objects objects have to be touching?
Yes, conduction does require direct contact between objects for heat transfer to occur. This is because heat is transferred through the collision of particles in direct contact with each other. If there is no direct contact, conduction cannot take place.
Is Convection is the flow of heat energy direct contact between molecules?
Convection is the transfer of heat through the movement of fluids or gases. It does not require direct contact between molecules, as the heat energy is carried by the movement of the fluid itself.
What is the method of heat transfer does not require a medium?
Radiation is the method of heat transfer that does not require a medium. Energy is transferred in the form of electromagnetic waves, such as light or infrared radiation, through empty space. This type of heat transfer can occur between objects that are not in direct contact with each other.
What does conduction and convection have in common?
Conduction and convection are both methods of heat transfer. They both require a material medium for the transfer to occur - conduction is through direct contact between materials, while convection involves the movement of fluids.
How are conduction convection and radaiton different form each other?
Conduction is the transfer of heat through direct contact between particles. Convection is the transfer of heat through the movement of fluid particles (liquid or gas). Radiation is the transfer of heat through electromagnetic waves and does not require a medium for propagation.
What type of force does not require direct contact?
Electromagnetic force does not require direct contact between objects. It can act over a distance, such as magnetic attractions and repulsions or electrical interactions between charged particles.
How is heat transfer by radiation different from both convection and conduction?
Heat transfer by radiation does not require a medium for transfer, as it can occur through electromagnetic waves. In contrast, convection involves the transfer of heat through the movement of fluids or gases, while conduction occurs through direct contact between materials. Radiation can occur in a vacuum, while convection and conduction require a medium.
What are the general character of non contact force's?
Non-contact forces do not require physical contact between objects to act. Examples include gravitational force, electrostatic force, and magnetic force. These forces can act over a distance and do not require direct contact between the objects involved.
Three methods of thermal energy transfer?
Conduction: Heat transfer through direct contact between objects with different temperatures. Convection: Heat transfer through the movement of fluids (liquids or gases) due to differences in temperature. Radiation: Heat transfer through electromagnetic waves that do not require a medium and can travel through a vacuum.
