Video Transcript
Reading Thermometers
In this video, we will learn how to
measure temperature in degrees Celsius using a thermometer and say whether it is
cold, cool, warm, or hot.
We use a thermometer to measure
temperature. If you’ve ever been ill and visited
the doctor, maybe you’ve had your temperature taken. A thermometer can tell us how hot
or cold we are. Sometimes when we’re ill, our
bodies get too hot. Doctors can give us medicine to
help our temperature go back to normal.
We can also use a thermometer to
tell us how hot or cold it is outside. Thermometers contain a special
liquid. And when the liquid heats up, it
rises. This is a hot day. The temperature is 30 degrees
Celsius. We can measure temperature in
degrees Celsius.
Thermometers have a scale. It looks just like a number
line. We read the scale in the same way
we would read a number line. We use it to help us read the
temperature. We find the level of the liquid
inside the thermometer, and we read across to the scale to find the temperature. When the temperature is zero
degrees Celsius, we often say it’s freezing. It is very cold because at zero
degrees Celsius, water freezes. We know if the temperature outside
is zero degrees or below zero degrees, it’s very cold.
On a hot day, the temperature is
usually above 30 degrees Celsius. 10 degrees Celsius would probably
be a cool day. We’d probably need our coats. And if the temperature was 20
degrees Celsius, we’d probably say it was a warm day.
Not all thermometers are the
same. The scale on this thermometer goes
up in 10s. Zero, 10, 20, 30. The scale could go up in twos, or
even in 20s. We need to be very careful when
we’re reading the scale. Let’s have a go at some questions
now and practice reading thermometers.
Jennifer, Liam, and Daniel are in
different parts of the world. Find the thermometer that shows
what the temperature is where they are.
This is Jennifer. And she’s saying, “It is cold
here.” We have to find or choose the
thermometer that shows what the temperature is like where Jennifer is. Which of the three thermometers
shows the temperature is cold? Let’s read the temperature on all
the thermometers to try and find the one which shows that it’s cold.
The temperature on the first
thermometer is between 10 and 20 degrees. Halfway between 10 and 20 degrees
is 15. And we’re two marks past 15. Two more than 15 is 17. The temperature on the first
thermometer is 17 degrees Celsius.
Let’s read the temperature on the
second thermometer. It’s somewhere between 30 and 40
degrees Celsius. The red line shows 35 degrees. And our temperature is two marks
below 35. Two less than 35 is 33.
The temperature on the third
thermometer is really easy to read. It’s at zero degrees Celsius. Which of these temperatures shows
that it’s cold outside? 17, 33, or zero? It’s this thermometer. When it’s zero degrees Celsius,
it’s cold outside. This is the thermometer that shows
the temperature where Jennifer is.
This is Liam. He says, “It is hot here.” Which thermometer shows the
temperature where Liam is? We know it’s not the third
thermometer because it shows zero degrees Celsius. That’s the temperature where
Jennifer is. We’ve already read the
thermometers, and we know the first one says 17 degrees Celsius. And the second thermometer shows 33
degrees Celsius. Which is hotter? 33 degrees or 17? It’s 33 degrees Celsius. This is the thermometer that shows
the temperature where Liam is.
This is Daniel. He says, “It is warm here.” We know that this thermometer shows
the temperature where Jennifer is. It’s cold where Jennifer is, and
it’s zero degrees Celsius. And we know that this thermometer,
which shows 33 degrees Celsius, which is hot, is the thermometer that shows the
temperature where Liam is. So, the thermometer that shows the
temperature where Daniel is must be the first one, which shows a temperature of 17
degrees Celsius. So, this is the thermometer that
shows the temperature where Daniel is. 17 degrees Celsius is warm.
So, this is the thermometer that
shows the temperature where Jennifer is. Zero degrees Celsius is cold. This is the thermometer that shows
the temperature where Liam is. 33 degrees Celsius is hot. And this is the thermometer that
shows the temperature where Daniel is. 17 degrees Celsius is warm.
Which thermometer shows 15 degrees
Celsius?
In this question, we’re shown three
different thermometers. We need to read the thermometers to
find the one which shows 15 degrees Celsius. The level of the liquid in the
first thermometer is level with the number 10 on the scale. This thermometer shows 10 degrees
Celsius. Which temperature does the second
thermometer show? Two marks above 20 is 22 degrees
Celsius. This isn’t the thermometer we’re
looking for either. Let’s see if the last one shows 15
degrees Celsius.
The level of the liquid in this
thermometer is halfway between 10 and 20, which is 15 degrees Celsius. This is the thermometer we’re
looking for. It shows 15 degrees Celsius.
These thermometers are
different. Look carefully and find which
thermometer shows the coldest temperature. Which thermometer shows the hottest
temperature?
Like the question says, we need to
look carefully at the scales on each thermometer. The scale on the first one goes
from zero to 10. Each of the divisions on this scale
is worth one. Let’s read the temperature. Zero, one, two, three, four. The temperature shown on
thermometer A is four degrees Celsius.
The scale on the second thermometer
is between zero and 50. The numbers marked on this scale go
up in 10s. Zero, 10, 20, 30, 40, 50. And the marks or the divisions in
between each multiple of 10 are worth five because half of 10 is five. Zero, five, 10, 15, 20, 25, 30, 35,
40, 45, 50. This scale goes up in fives. The temperature on this scale is
between 35 and 40, probably around 37 degrees Celsius.
Let’s read the third
thermometer. The scale goes up in 10s. Zero, 10, 20, 30, 40, 50, 60, 70,
80, 90, 100. The liquid on this thermometer is
level with the halfway mark between 40 and 50. Halfway between 40 and 50 is 45
degrees Celsius.
Now, we know what the temperature
is on each thermometer, we can find the coldest temperature, and the hottest. Which thermometer shows the coldest
temperature? It’s thermometer A. Four degrees is colder than 37
degrees and 45 degrees Celsius. And which thermometer shows the
hottest temperature? It’s thermometer C. 45 degrees Celsius is hotter than
37 degrees and four degrees. The thermometer that shows the
coldest temperature is A. And the thermometer which shows the
hottest temperature is C.
What have we learned in this
video? We’ve learned how to read the
temperature on a thermometer in degree Celsius and how to tell whether it is cold,
cool, warm, or hot.
