Q6. Give reasons for the following
i) Table mats are made from cane or plastics.ii)Ventilators are situated close to the ceiling.iii) Handles of bikes and scooters are covered with rubber.iv) We cannot use laboratory thermometer to measure our body temperature.v) We prefer to wear white clothes in summervi) Heating coils of a room heater have a shiny curved metal surface.vii) Solar cookers are painted black from inside
1. Table mats are usually made up of canes or plastic because canes or plastics are easy to clean and are also cheaper. They are also very convenient to use. Moreover, canes or plastics have a good durability.
2. Ventilators in houses are situated near the ceiling because the air we breathe out is hotter and thus lighter in weight. So, they can easily be removed from the houses by these outlets for the stale and the fresh air enters the room by doors or windows.
3. The handles of bikes and scooters are made from plastic because they make easy to hold or grip in our hand and they partly absorbs vibration. Moreover, plastics are bad conductor of heat, so during summer they don’t heat more when kept under sun.
4. We cannot use a laboratory thermometer for measuring our body temperature because the medical thermometer has a specific thermometer regarding the temperature range, accuracy, gradations, and dimension whereas laboratory thermometers does not have these features.
5. People prefer to wear white cloths during summer because white or light colours reflect most of the heat.
6. Heating coils of a room heater have a shining covered metal surface in order that they absorb very little heat and reflect most of it and thus we get heated during winter.
7. As we know that black colour absorbs heat and also does not allow heat to escape. Therefore, the solar cooker is painted black so that maximum heat energy from sun is absorbed and does not escape from it and thus food is well cooked
2. Ventilators in houses are situated near the ceiling because the air we breathe out is hotter and thus lighter in weight. So, they can easily be removed from the houses by these outlets for the stale and the fresh air enters the room by doors or windows.
3. The handles of bikes and scooters are made from plastic because they make easy to hold or grip in our hand and they partly absorbs vibration. Moreover, plastics are bad conductor of heat, so during summer they don’t heat more when kept under sun.
4. We cannot use a laboratory thermometer for measuring our body temperature because the medical thermometer has a specific thermometer regarding the temperature range, accuracy, gradations, and dimension whereas laboratory thermometers does not have these features.
5. People prefer to wear white cloths during summer because white or light colours reflect most of the heat.
6. Heating coils of a room heater have a shining covered metal surface in order that they absorb very little heat and reflect most of it and thus we get heated during winter.
7. As we know that black colour absorbs heat and also does not allow heat to escape. Therefore, the solar cooker is painted black so that maximum heat energy from sun is absorbed and does not escape from it and thus food is well cooked