What is the mass of the
leaf? One gram or one kilogram.
Our question asks us what the
mass of the leaf is. In other words, how heavy is
it? Now, if the question just asked
us this and didn’t give us any clues, then we might find it quite difficult to
answer. But we can see at the bottom
we’ve got two answers to choose from, which makes it easier for us. Both our answers have the
number one in front of them. The mass of the leaf is one
something. But is it one gram or one
kilogram? We need to choose the correct
unit of measurement.
To help us, let’s remind
ourselves of some objects that weigh about the same as one gram and one
kilogram. One gram is about the same as a
stick of chewing gum. And a large dictionary is about
the same as one kilogram. Now, we’ve thought about these
everyday objects. It can help us think about the
mass of the leaf. We can see straight away, can’t
we, that one gram is quite light. And although one kilogram isn’t
really, really heavy, it’s still a lot heavier than a gram.
So what do you think, is the
mass of the leaf more likely to be the same as a stick of chewing gum or a big
dictionary? It’s more likely to weigh one
gram, isn’t it? Think about the way that leaves
fall from the tree slowly and get blown around by the wind. We can pick lots and lots of
them up in our hands, and it doesn’t feel heavy at all. A leaf is very light, and so we
know the mass of the leaf is one gram.