How to make a thermometer?

Here, I will teach you to make a thermometer, and measure the temperature by using the volume of water that expands when heated and contracts when cooled.

Materials and methods

1. Prepare a bottle with a cork, a straw (preferably transparent) and some plasticine.

2. First make a hole in the cork, insert the straw into the hole, and then fill the bottle with water. It is best to add a little color to the water, using advertising color, food coloring and ink.

3. Put the cork and straw into the bottle, and then seal the holes in the bottle mouth and cork with plasticine.

Put the bottle in a warm place, and the level of colored water in the straw will rise.

Put the bottle in a cold place, and the water level will drop.

6. The first few steps only let you make a simple thermometer. In order to make your homemade thermometer more accurate and exquisite, stick a piece of cardboard on the straw. Borrow a real thermometer and put it in the room, and test the room temperature of several different rooms together with the homemade thermometer. With reference to a real thermometer, you can know the actual temperature at that time, and then write the scale and figures of the temperature on the cardboard at the same height as the straw. After repeated many times at different temperatures, you can create a scale on the cardboard.

In this way, a real thermometer was born from your hand. You can use it to find out the coldest and hottest places in your home, or you can use a homemade thermometer to record the daily temperature and see how the weather changes.