To measure temperature there is an element inside the thermometer. It is mercury. Mercury is a toxic substance if a thermometer breaks. So, we should handle a thermometer with care. There are two types of thermometer- laboratory, digital, clinical, and infrared thermometer. We will also learn about the uses of all these different kinds of thermometers.

In this virtual tour, we will learn about what convection is. It is basically a transfer of heat from one place to another. When water is heated the molecules of water in the lower level become hot and they go up, and empty space occupies with cool atoms of water from upper layers, this process continues until all the atoms of water are heated, this process is called convection of water.

When there is no fire, the air atoms move randomly above the wood. When we lit the fire the atoms just above the fire started moving speedily. The air near the heat source gets heated up and rises up. The vacant space will be replaced by cool air from the surrounding. This whole process is called the convection of air.

The Density of hot air is less than the density of the cool air, so the hot air always goes up. The cool air from the sea occupies the space left by the hot air. Air coming from the sea is called the sea breeze. The land breeze flows from the land towards the sea during the day. The sea breeze flows from the sea towards the land during the night.

Have you ever wondered why we feel hotter when we wear black color clothes during summers? It’s because black color absorbs all the seven rays from sunlight means more heat-absorbing and while white color doesn’t absorb any rays which mean no or very less heat absorbing.