Teacher Troy stands in front of a blackboard. On a table in front of them there's a scale, a brick, a measuring jar, some cookies, and a milk carton.

Teacher Troy is in his thirties, bald and with a shadow of a beard. He wears a blue Homework Help T-shirt.

He says HI TVO KIDS.
THIS IS TEACHER TROY, WE'RE
GOING TO BE TALKING ABOUT
MEASUREMENT.
MEASUREMENT DEALS WITH
COMPARISON.
COMPARISON TO A STANDARD OF
UNITS.
TODAY WE'RE GOING TO BE DEALING
WITH SOLIDS AND LIQUIDS.
NOW WHEN WE START WITH SOLIDS,
SOLIDS ARE USUALLY MEASURED IN
GRAMS OR KILOGRAMS.
SO I'M GOING TO GRAB THIS STACK
OF COOKIES, AND PUT IT ON THE
SCALE.
AND THE READING IS ABOUT 50
GRAMS.
SO AS YOU SEE, GRAMS MEASURE
THINGS THAT ARE VERY SMALL.
NOW IF WE TAKE THE COOKIES OFF,
AND I HAVE A NICE BIG BRICK
HERE.
THE BRICK.
LET'S PUT IT ON THE SCALE.
MAKES THE SCALE GO A LITTLE
CRAZY AND IT DOESN'T HELP
MEASURE IT.
SO WHAT THAT MEANS IS, THIS
BRICK NEEDS TO BE MEASURED IN
SOMETHING LARGER THAN GRAMS.
AND THAT'S WHY WE WOULD USE
KILOGRAMS.
AND THIS BRICK WEIGHS
APPROXIMATELY TWO KILOGRAMS.
SO KILOGRAMS MEASURE THINGS THAT
ARE REALLY LARGE, AND GRAMS
MEASURE THINGS THAT ARE SMALL.
NOW WHEN WE'RE DEALING WITH
LIQUID.
IMAGINE I WANTED TO TAKE THIS
LIQUID AND POUR IT ONTO THE
SCALE.
IT WOULD COVER IT, IT WOULD MAKE
A BIG MESS.
SO THAT'S WHY WE DON'T POUR IT
ON HERE.
TO MEASURE LIQUIDS WE NEED A
CONTAINER SUCH AS THIS MEASURING
CUP.
SO WHEN I POUR THIS MILK IN, AS
YOU SEE ON THE SIDE, AS IT GETS
HIGHER, SO RIGHT THERE.
IT STOPPED AT THE NUMBER
APPROXIMATELY 200.
SO THAT TELLS US THAT WE HAVE
200 MILLILITRES.
AND LIQUIDS WE MEASURE IN EITHER
MILLILITRES BECAUSE IT'S A SMALL
QUANTITY OR LITRES.
AND YOU KNOW WE HEAR ABOUT
LITRES ALL THE TIME.
ESPECIALLY IN THE NEWS WHEN WE
TALK ABOUT GAS.
SO THE AMOUNT OF, WHEN YOU'RE
MEASURING SOMETHING THAT'S SMALL
WITH LITRES, IT'S MILLILITRES.
WHEN YOU'RE MEASURING SOMETHING
THAT'S LARGE, YOU'RE USING
LITRES.
SO MASS IS DIFFERENT FOR SOLIDS.
CAPACITY IS USED FOR LIQUIDS.
BECAUSE WE CAN'T ACTUALLY POUR
THIS ON THE SCALE.
SO JUST TO KNOW THE DIFFERENCE.
I'M TEACHER TROY AND I HOPE THAT
HELPS.