A trapped layer of air.
Air is a poor conductor of heat. If you can keep a static (non moving) laver of air next to your skin then that layer of air will keep you at a more comfortable temperature. To keep warm natural fibers/fibres like wool trap air next to the body. Now many synthetic fibers do the same. That means the body warms that layer of air that is trapped and the body stays at a comfortable temperature even if it is cold outside. We are always colder in wind that stops us from holding that trapped layer of air close to our skin. We button up or zip up our jacket trying to keep our air layer intact.
The reverse is also true. Wearing loose cotton clothing in extremely hot weather means that the trapped layer of air stops you from feeling the full strength of the outside heat. Usually in hot weather we like a breeze to blow away the air near our body and evaporate the perspiration on our skin. The evaporated water carries away heat from our skin.
Cotton is a natural fiber that will trap air next to your skin and keep your feet warm.
Ice will typically melt faster on a metal board compared to a plastic board. This is because metal is a better conductor of heat, allowing it to transfer heat more efficiently to the ice. The plastic board acts as an insulator, slowing down the transfer of heat to the ice and thereby slowing the melting process.
Glass is a better insulator of heat compared to clay. Clay transfers heat more efficiently due to its higher thermal conductivity.
Metal is a better conductor of heat compared to plastic. Metals have free electrons that can carry heat energy quickly, while plastic is an insulator and does not allow heat to easily pass through it. This is why metal objects feel colder or hotter to the touch compared to plastic objects at the same temperature.
Cotton wool has a very low density and has thousands of pockets to trap air in. Because of this, cotton wool is a good insulator, but there are others that are better. As a rule of thumb, the lower the density, the better the insulator. There are virtually no exceptions to this.
Glass is a better conductor of heat compared to plastic. This means heat travels more easily through glass than plastic, allowing glass to heat up or cool down faster when in contact with a heat source or a cold surface.
cotton
aluimum foil
Ice will typically melt faster on a metal board compared to a plastic board. This is because metal is a better conductor of heat, allowing it to transfer heat more efficiently to the ice. The plastic board acts as an insulator, slowing down the transfer of heat to the ice and thereby slowing the melting process.
Air is the best insulator among the options listed. It has low thermal conductivity, meaning it does not easily transfer heat. Thermocol, cotton, and aluminium are not as effective as insulators compared to air.
Glass is a better insulator of heat compared to clay. Clay transfers heat more efficiently due to its higher thermal conductivity.
Copper has a much higher thermal conductivity compared to cotton wool, so copper would have a higher U value. Thermal conductivity is a measure of how easily heat passes through a material, with higher values indicating better heat conduction. Cotton wool, being a less conductive material, would have a lower U value.
Metal is a better conductor of heat compared to plastic. Metals have free electrons that can carry heat energy quickly, while plastic is an insulator and does not allow heat to easily pass through it. This is why metal objects feel colder or hotter to the touch compared to plastic objects at the same temperature.
Cotton wool has a very low density and has thousands of pockets to trap air in. Because of this, cotton wool is a good insulator, but there are others that are better. As a rule of thumb, the lower the density, the better the insulator. There are virtually no exceptions to this.
Copper is a better heat conductor compared to aluminum. Copper has higher thermal conductivity, meaning it can transfer heat more efficiently than aluminum. This is why copper is commonly used in applications that require high heat transfer, such as heat exchangers and cookware.
Cotton traps heat by creating pockets of air between its fibers, which serves as insulation that retains body heat. When these air pockets are warmed by body heat, the cotton material then traps and holds that warmth close to the body. This is why cotton clothing can help keep you warm in cold temperatures.
Glass is a better conductor of heat compared to plastic. This means heat travels more easily through glass than plastic, allowing glass to heat up or cool down faster when in contact with a heat source or a cold surface.
No, water is a better conductor of heat than glass. Water has a higher thermal conductivity, allowing it to transfer heat more efficiently than glass. Glass is a relatively poor conductor of heat compared to water.