To determine which drawing is a net of a cube, we need to check if the shape can be folded into a closed box with 6 square faces without any overlaps or gaps.
Step 1: Count the squares
A cube has 6 faces, so a valid net must have exactly 6 squares.
- The first drawing (left) has 6 squares.
- The second drawing (middle) has 6 squares.
- The third drawing (right) has 6 squares.
Since all of them have the correct number of squares, we must look at how they are arranged.
Step 2: Analyze the first drawing (left)
This shape looks like a cross with an extra square attached to the top right.
- Imagine the vertical column of four squares forms the sides of the cube (front, bottom, back, top).
- The square on the left folds up to become the left side.
- The square on the top right folds over to become the right side.
- When you fold this shape, all faces meet perfectly, and there are no overlapping squares. This is a valid net.
Step 3: Analyze the second drawing (middle)
This shape has a row of four squares with one square below the first one and one square below the last one.
- If you try to fold the row of four into a tube (the sides), the two bottom squares will both try to fold in to cover the same bottom opening.
- Because two faces are trying to occupy the same space (overlap), and there is no square to cover the top opening, this cannot form a cube.
Step 4: Analyze the third drawing (right)
This shape has a long row of five squares with one square sticking out on top.
- A rule for cube nets is that you cannot have a straight line of more than 4 squares.
- If you fold the row of five, the squares will wrap around and overlap each other before you can close the shape properly. Specifically, the fifth square would overlap with the first or second square depending on how you fold it, leaving gaps elsewhere. Therefore, this is not a valid net.
Conclusion:
Only the first drawing can be folded into a cube.
Final Answer:
The first drawing (a)
Parent Tip: Review the logic above to help your child master the concept of nets worksheet.
