Question 21 MarkEvery warm substance continuously emits heat in all directions around itself.AnswerTrueView full question & answer→
Question 31 MarkA convection current always travels down wards.AnswerFalse – A convection current always travels upwards.View full question & answer→
Question 41 MarkHot water is heavier than cold water.AnswerFalse – Hot water is lighter than cold water.View full question & answer→
Question 51 MarkDuring conduction, particles of the conductor leave their original place.AnswerFalse. During conduction, particles of the conductor do not leave their original place, but only vibrate in their own place.View full question & answer→
Question 71 MarkDuring radiation, the particles of the medium vibrate.AnswerTrueView full question & answer→
Question 81 MarkRadiation of heat depends upon the colours of the outer surface of the body.AnswerTrueView full question & answer→
Question 91 MarkIn a thermos flask, hot things remain hot and cold things become warm.AnswerFalse. In a thermos flask, hot things remain hot and cold things remain cold.View full question & answer→