VR Tour For Std. 7 Ch. 4: Heat
What's Included in Virtual tour of this chapter
Temperature is the degree of hotness or coldness measured on a definite scale. The thermometer is a device used to measure temperature. Convection takes place when heated molecules move from one place to another, taking the heat with them. We will also learn about the convection of air which is when the air near the heat source gets heated up and rises up. The wind blowing from the sea towards the land is called Sea Breeze and the wind blowing from the land towards the sea is called the land breeze. We will also understand the science behind why black color absorbs more heat than white.
Virtual tour 1: Types of the thermometer
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.
Virtual tour 2: The Convection of water
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.
Virtual tour 3: The Convection of air
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.
Virtual tour 4: Sea breeze and land breeze
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.
Virtual tour 5: Heat absorption- Color Matters
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.