Give reasons.
(a) We can feel the heat of a table lamp, under it.
(b) The upper layers of water in a deep well are cool but those in a pond are warm.
(c) Sawdust is a bad conductor of heat.
Give reasons.
(a) We can feel the heat of a table lamp, under it.
(b) The upper layers of water in a deep well are cool but those in a pond are warm.
(c) Sawdust is a bad conductor of heat.
(a) A glowing table lamp produces light and heat. Some part of this heat is felt under the lamp by the process of radiation.
(b) The upper layers of water in a deep well are not directly exposed to sunlight. So, they remain cool. However, the upper layers of water in a pond are directly exposed to the sunlight for longer duration. So, they remain warm.
(c) Sawdust is a combination of wood particles and air. Both wood and air are bad conductors of heat. Again, wood particles are loosely packed in sawdust so heat is transferred at very slow rate. Hence, sawdust is a bad conductor of heat.
(a) A glowing table lamp produces light and heat. Some part of this heat is felt under the lamp by the process of radiation.
(b) The upper layers of water in a deep well are not directly exposed to sunlight. So, they remain cool. However, the upper layers of water in a pond are directly exposed to the sunlight for longer duration. So, they remain warm.
(c) Sawdust is a combination of wood particles and air. Both wood and air are bad conductors of heat. Again, wood particles are loosely packed in sawdust so heat is transferred at very slow rate. Hence, sawdust is a bad conductor of heat.
