permukaan rata · melengkung = flat and curved surfaces A 3D shape can have flat surfaces, curved surfaces, or both. Feel them with your hand: a flat surface can lie still on the table, while a curved one lets the shape roll. Example: a cylinder has 2 flat surfaces and 1 curved surface, so 2 + 1 = 3 surfaces in all. Watch out: a cone has 1 flat surface and 1 curved surface, so it can roll too.
Langkah 2
Kira bucu dan sisi lurus
Kubus, kuboid dan piramid boleh dibezakan dengan bilangan bucu, sisi lurus dan bentuk permukaannya.
permukaan + bucu + sisi lurus
bucu dan sisi lurus = 顶点和直边 正方体、长方体和四角锥可以用顶点、直边和面的形状来分辨。顶点是尖尖的角，直边是两个面相交的线。 例子：四角锥底部有 4 个顶点，加上顶端 1 个，共 4 + 1 = 5 个顶点。 注意：数顶点时容易重复，可以用笔在数过的角上点一下。
bucu dan sisi lurus = vertices and straight edges Cubes, cuboids and pyramids can be told apart by counting vertices and straight edges and by looking at the shapes of their faces. A vertex is a pointed corner; an edge is where two faces meet. Example: a square pyramid has 4 vertices at the base and 1 at the top, so 4 + 1 = 5 vertices. Watch out: corners are easy to count twice, so tick each one as you go.
Langkah 3
Kenal bentuk yang boleh bergolek
Silinder dan kon mempunyai permukaan melengkung, jadi kedua-duanya boleh bergolek dalam arah tertentu.
boleh bergolek = can roll Cylinders and cones have a curved surface, so they can roll. A cylinder on its side rolls in a straight line, while a cone rolls in a circle around its tip. A cube has only flat faces, so it slides instead. Example: 2 tins and 1 ice cream cone on a table give 2 + 1 = 3 things that can roll. Watch out: a cylinder standing on its flat end will not roll; it must lie on its side.
Semak cepat · Soalan 1 / 2
Cuba sendiri
Pilih jawapan. Jika belum tepat, baca petunjuk dan cuba lagi.
Bentuk yang mempunyai 6 permukaan rata sama besar ialah…
6 permukaan rata sama besar = 6 个一样大的平面 题目问：哪一个形状有 6 个一样大的平面。线索有两个：所有面都是平的，而且大小都一样。 例子：每个面贴 2 张贴纸，6 个面共贴 2 + 2 + 2 + 2 + 2 + 2 = 12 张。 注意：长方体也有 6 个平面，但它的面不一定一样大。
6 permukaan rata sama besar = 6 equal flat faces The question asks which shape has 6 flat faces that are all the same size. There are two clues: every face is flat, and all faces are equal. Example: 2 stickers on each of 6 faces need 2 + 2 + 2 + 2 + 2 + 2 = 12 stickers. Watch out: a cuboid also has 6 flat faces, but they are not always equal in size.
Semak cepat · Soalan 2 / 2
Cuba sendiri
Pilih jawapan. Jika belum tepat, baca petunjuk dan cuba lagi.
bilangan bucu kuboid = number of vertices of a cuboid The question asks how many vertices a cuboid has. Hold a box and count the corners on the top layer, then the corners on the bottom layer, and add them. Example: a cube has 4 vertices on top and 4 below, so 4 + 4 = 8 vertices. Watch out: vertices are corners and edges are lines, so do not give the number of edges instead.
Ringkasan
Syabas!
Kamu telah belajar tentang Kenal Pasti Bentuk 3D.
Ingat: lihat permukaan; kira bucu dan sisi lurus; kenal bentuk yang boleh bergolek.
