### Video Transcript

What is 330 kelvin in degrees
Celsius?

Okay, so in this exercise, we
want to convert a temperature in the kelvin scale to an equivalent one in the
Celsius scale. To do this, we can start by
recalling the particular values that these two scales, the kelvin and the
Celsius scale, give to describe the temperatures of absolute zero and the
temperature at which water freezes. Now, the kelvin scale was
designed around absolute zero, so that absolute zero is at zero kelvin. The equivalent temperature on
the Celsius scale is negative 273. Then, if we consider water
freezing or equivalently ice melting, that happens at 273 kelvin. And then, on the Celsius scale,
it happens at zero.

So, on both of these scales, on
both the kelvin and the Celsius scale, we add 273 to go from the temperature at
absolute zero to the temperature at which water freezes. This tells us that if we have a
temperature, in general, in kelvin, we can call it 𝑇 sub K, then if we take
that temperature and subtract 273 from it, we’ll get the equivalent temperature
in degrees Celsius. So, given a temperature in
kelvin, if we take away 273, we’ll get the equivalent temperature in degrees
Celsius. And we can test this out using
our temperature scale. Over here, we have 273 kelvin,
and then if we subtract 273, we get zero, and that’s degrees Celsius. And then an absolute zero, zero
kelvin, minus 273 is negative 273 degrees Celsius.

Now, in our exercise, we want
to take 330 kelvin and convert that to degrees Celsius. This means, in place of 𝑇 sub
K, we’ll write 330, and we’ll leave off the units as we normally do in
converting between temperature scales. So, we take our temperature in
kelvin and then we subtract 273 from it. And that, our equation says, is
the equivalent temperature in degrees Celsius. Well, 330 minus 273 is 57. And it’s at this point, at the
end, that we put on our units. They’re degrees Celsius. And we found our answer. 330 kelvin is 57 degrees
Celsius.