Science and Discoveries in Europe

Základná škola J. Lipského s MŠ Trenčianske

StankovceSlovakia - 2011

Project Comenius

Science through the four elements – fire, air, earth and water

What is a thermometer?

• „thermo" means

heat and "meter" means to measure

• a thermometer measures the temperature of things

• it is usually a glass or plastic tube with a scale of measurement on the side of it (a bit like a ruler).

At first pupils found lots of information about it

• Celsius scale is named after Swedish Anders Celsius who developed it in 1742. It is divided into 100 degrees. On the Celsius scale the freezing point of water is 0 degrees Celsius (C) and the boiling point of water is 100 degrees C

• Fahrenheit scale is named after German Gabriel Fahrenheit who developed his scale in 1724. Ice freezes at 32 degrees Fahrenheit (F ) and water boils at 212 degrees F

• Kelvin scale is named after Lord Kelvin. His scale starts at 0 degrees Kelvin, which is called absolute temperature (- 273,15°C )

Liquid thermometer

• in bulb thermometer, you can see a thin red or silver line

• it can be coloured alcohol or mercury

• the line grows longer when it is hotter

• it goes down when it is colder

Types of thermometers• outside bulb

thermometer shows how hot or cold it is outside

• the thermometer in the thermostat tells the heat or air conditioning when you turn on and off

• the thermometer in the oven keeps the oven at a set hot temperature when it is turned on

• the thermometer in the refrigerator and freezer maintains a set cold temperature

• the body thermometer measures body temperature to let you know if you have a fever (more than 37°C)

We tried it

If you put a bulb thermometer in your mouth, or somewhere else that’s quite warm, the red liquid inside the bulb gets warmer and expands moving up the tube.

The girl was healthy, her temperature was only 36,2°C.

• because mercury is a poisonous metallic liquid most medical thermometers have red alcohol in them

• or we use digital thermometer

(this girl is also healthy without any fever)

The pupils measured and compared the temperatureIn the classroom: 25°C

Outside–sunny place: 30°C

Outside-northern side: 25°C

ExperimentHow does a thermometer work?

We need: • a small jar with

cold and coloured water

• a lid that has a small hole

• a thin straw• chewing gum or

blue tack • a bigger jar or bowl

with hot water

Instructions

1 Fit the thin straw through the hole in the lid of the jar, use blue tack or chewing gum so that it is watertight. Do this to both sides of the lid - top and bottom.

2 Pour cold water into

a small jar and colour it.

3 Screw the lid on the jar.

4 Pour hot water into bigger jar.

5 Put the small jar into the jar or bowl with hot water.

We were surprised - coloured water got warmer so it expanded and moved up the straw – like in a thermometer.

This group was not so succesful with the same experiment – little hot water in the bowl and coloured water could not expand.

Tento projekt bol zrealizovaný vďaka finančnej podpore Európskej komisie