i. The hotness of an object is determined by its temperature.
ii. Temperature is measured in degree celsius.
iii. A cold steel spoon is dipped in a cup of hot milk. It transfers heat to its other end by the process of conduction.
iv. Land breeze blows during night.
v. Sea breeze blows during day.
vi. Dark coloured clothes are preferred during winter.
vii. Poor conductors are known as insulators.
i. Temperature of boiling water cannot be measured by a clinical thermometer. True
ii. Medium is required for transfer of heat by the process of radiation. False
iii. Clothes of dark colours absorb heat better than clothes of light colours. True
iv. Light coloured clothes are preferred during summer. True
v. We should hold the thermometer by the bulb while holding it. False
vi. The bulb of laboratory thermometer should not touch the bottom or the sides of the container. True
Ans. Smoke will go upward.
Ans. A reliable measure of the hotness of an object is its temperature.
Ans. Thermometer is used to measure temperature.
Ans. Silver stuff in a thermometer is mercury.
Ans. India has adopted the celsius scale.
Ans. The normal temperature of human body is 37°C.
Ans. The range of a laboratory thermometer is generally from –10°C to 110°C.
Ans. It prevents mercury level from falling on its own.
Ans. Heat flows from a hotter object to a colder object.
Ans. The transfer of heat by radiation does not require any medium.
Ans. Yes, all hot bodies radiate heat.
Ans. In liquids and gases the heat is transferred by convection.
Ans. Heat will not be transferred if the temperature of two objects is the same.
Ans. Mercury level should be below 35°C.
Ans. In solids, generally, the heat is transferred by the process of conduction.
Ans. Thermometer should be washed before and after use, preferably with an antiseptic solution.
Ans. The process by which heat is transferred from the hotter end to the colder end of an object is known as conduction.
Ans. The materials which do not allow heat to pass through them easily are insulators of heat. Example: plastic and wood.
Ans. The materials which allow heat to pass through them easily are conductors of heat. Example: aluminum, iron and copper.