Rohan wants to test whether a white object or a black object would heat up faster in the Sun. The given picture shows you his experiment. These thermometers were left out in the Sun for minutes. Which of the following statements is true?
Important Questions on Heat
The bimetallic strip made up of aluminium and copper, when heated bends in the direction shown here. Which metal expands more when the two are heated at the same temperature?
Statement 1: An iron ball at is dropped in a mug containing water at . Then the heat will flow from the water to the iron ball.
Statement 2: In convection, heated molecules of a liquid themselves move to carry heat from the hot region to the cold region.
A thermos flask is a household item that is used to keep things warm or cold for a long time. What is the use of silvered wall in thermos flask?
(i) Two thin woollen sweaters are warmer than a thick woollen sweater.
(ii) It saves fuel if we cook food in a vessel which is blackened at the bottom and polished from the sides.
(iii) The cable wires between two poles are left loose, because in summers the wires may not break on expanding.
A saucepan is usually made up of two different materials, and . Identify and .
Two glass test tubes are heated from two different places of the test tubes. In which test tube will all the water heat up first?
A hot liquid is carefully poured into a beaker. The graph shows how its temperature changes as it cools towards room temperature. Which process(es) is/are taking place at region ?
