Temperature tells us how hot or cold something is.
- Tea is hot, it has a higher temperature.
- Ice cream is cold; it has a lower temperature.
- Soup is hot, it has a higher temperature.
- Juice is cold, it has a lower temperature.
- By slightly touching the above objects, we can easily say whether it is hot or cold.
- Hot objects have higher temperatures.
- Cold objects have lower temperatures.
Hot and Cold whether
- When we go out on a summer afternoon, we feel very hot.
- It means the temperature is high on a summer day.
- When we go out on a snowy evening, we feel very cold.
- It means the temperature is low on a snowy day.
- By touching an object, we can identify whether it is hot or cold, but we can’t measure the temperature of the object. Because temperature is the degree of hotness or coldness.
- We can measure the temperature by using an instrument called thermometer.
- Thermometer is a device used to measure Temperature.
Parts of the Thermometer:
- Glass tube: Glass tube is a long cylindrical tube that is connected to the bulb.
- Bulb with a liquid: The bulb is the lowest part of the thermometer, and has a spherical shape. Here, Mercury stays in liquid form. When the temperature is getting high, mercury in the bulb moves up in the glass tube.
- Temperature scales: There are marked scales with numbers on both sides with respect to units of the temperature.
- There are mainly two types of units of Temperature on a thermometer–
- ℃ – C stands for Celsius
- ℉ – F stands for Fahrenheit
Did you know?
Celsius and Fahrenheit are the names of the people who invented each of these units.
- United States and some other countries use the Fahrenheit unit.
- Rest of the countries in the world use Celsius unit.
Relation between Fahrenheit and Celsius:
32 ℉ = 0 ℃
- 32 ℉ is equal to 0 ℃.
- In India we use a Celsius unit to measure temperature.
How to read Thermometer:
- We will measure the temperature of the boiling water.
- After putting the thermometer in the hot water, the thermometer’s mercury level reached at the number 100.
- Water boils at 100℃ temperature. It’s too hot.
- We will measure the temperature of the ice.
- After putting the thermometer on the cold ice, the thermometer’s mercury level reached at the number 0.
- Water freezes into ice at 0℃ temperature. It’s too cold.
- We will measure the temperature of the normal glass of water.
- After putting the thermometer in the normal glass of water, the thermometer’s mercury level reached at the number 20.
- Temperature of the glass of water is 20℃. It’s a normal temperature.
Different types of Thermometers:
Freeze: To become hard (and often change into ice) because
We made a snowman in our balcony. It is frozen and stands like statue.
Did you know?