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## 5th grade

# Measuring volume with unit cubes

Explore the concept of volume, emphasizing that it's a measure of how much space something takes up. Practice the idea of measuring volume in cubic units, like cubic feet or cubic inches, by counting the number of unit cubes that fit into a 3D shape. Created by Sal Khan.

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- If the radius of the base of right circular cylinder is halved. keeping the height same. what is the ratio of the volume of the reduced cylinder to that of the original.(21 votes)
- upvote if you like ice cream or video games(16 votes)
- who likes lemonade(12 votes)
- pink lemonade is better(7 votes)

- How many cubes are in 1 layer(9 votes)
- Depends. If it a 6 by 6 by 6, it would be 36 in one layer(6 votes)

- are there any other videos on this?

:)(8 votes)- Yes, there are many other videos on this(2 votes)

- I used to think volume is hard but all you have to do is multiply.(6 votes)
- So in a 3d world when you try to solve a problem, remember to also think about the parts you cannot see, like the back, bottom, and sometimes the sides is what you should also think when trying to solve problems like these.(4 votes)
- khan academy is a really good academy(5 votes)
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- but if i want to make a bigger volume square i would get bigger results teha change i every dimension(4 votes)
- Hi!

When the dimensions of the shape, such as radius, height, or length change, both surface area and volume also change. However, the volume of the object always changes more than the surface area for the same change in dimensions!

Credits: study.com

Hope this helped! :)(0 votes)

## Video transcript

We are asked, what is
the volume of this box? And they tell us that
each cube is a cubic foot. So just as a reminder,
volume is a measure of how much space does
something take up. And it's usually
measured in cubic units. And here we're talking
about cubic feet. And when they say that
each cube is a cubic foot, they're saying that each
of these little boxes, each of these cubes here, is
exactly a 1 foot by 1 foot by 1 foot cube. We're in three
dimensions right now. We're talking about
three dimensions. 3D, you literally
need three dimensions. You need how tall you
are, how wide you are, and how deep you are. And for a cubic foot, each
of those dimensions is one. So each of these
are one cubic foot. The entire shape has one,
two, three, four, five, six cubic feet in it. So the volume of this
entire box is 6 cubic feet. And you see right here
the unit says feet, and it has a
superscript here of 3. This is feet to the third power. You could view this as
feet times feet times feet, or cubic feet. So this is 6 cubic feet. Let's do a few more of these. What is the volume
of this shape? So this one is quite
interesting right over here. You have-- let's see
if we can count these. So you have one, two, three,
four, five, six, seven, eight unit boxes,
or I guess these are cubic inches
for this example. So we have 8 cubic inches. This is a lot of fun, especially
when we get to rotate it. So here, each cube is
a cubic foot again. So we have one, two,
three cubic feet. Let's do one more of these. I like the ones that have
these kind of crazy shapes that we have to rotate to be
able to see all the boxes. So each of these
is a cubic meter, which means that in each
dimension, each of these boxes is a 1 by 1 by 1 meter. But how many boxes are there? Let's see. We have one. We have one. Let me see if I can get a view
where I can look at it better. We have one, two, three,
four, five, six boxes. So the total volume
here is 6 cubic meters.