Front, top and side views

The idea

As a projection is not made by a unique object, three mutually perpendicular projections are used: the front view (vertical plane), top view (horizontal plane) and side view (side plane).

A round hole

A board has a round hole. You push a solid straight through the hole, without turning it.

Which solids can go through?

• Only a ball
• A ball, a can or a cone
• Only a can

Which solid is it?

Each solid stands on the floor of a room. Its shadow on the floor is its top view. Tap a solid to see its three views.

Which block is it?

A drawing sheet shows the three views of a block as dashed squares. Tap blocks A, B and C and compare their views with the sheet.

Three views of a solid

A projection is not made by a unique object, so we take three mutually perpendicular projections: the front view (projection on the vertical plane), the top view (on the horizontal plane) and the side view (on the side plane).

An object pushed straight through a plane makes a hole with the shape of its projection. A round hole fits a ball, a can or a cone.

Blocks A and C looked the same from the front and from the top. Only the side view told them apart.

Notes

A projection is not made by a unique object, so we use three mutually perpendicular projections: the front view, the top view and the side view.

Check yourself

This block is made of cubes. Which drawing is its front view?

This block has 4 cubes. How many squares are in its top view?

Answer: 3 squares

From above we see the row of 3 cubes. The cube on the left end has another cube on top, but from above they make one square. 3 squares.

The front view of a solid is a rectangle. Priya says, "It must be a cuboid." Is she right?

Blocks A and C have the same front view and the same top view. Which view tells them apart?

• Drawing A — correct. Yes! From the front you see the steps: 3 squares tall on the left, then 2, then 1.
• Drawing B. B is the top view: seen from above you see only a row of 3 squares.
• Drawing C. C is the side view: seen from the right you see only the tall column of 3 squares.
• Yes. Only a cuboid has a rectangle as a view.. A cylinder standing on its base also has a rectangle as its front view.
• No. A cylinder standing on its base also has a rectangle as its front view. — correct. Yes! Different solids can give the same projection. That is why we need more than one view.
• No. A rectangle can never be the front view of a solid.. It can. A cuboid, for example, has a rectangle as its front view.
• The front view. Both blocks give the same front view, so it cannot tell them apart.
• The top view. Both blocks give the same top view too.
• The side view — correct. Yes! In A the extra cube is at the front and in C it is at the back. Only the side view shows that.