Question 1: Draw an orthographic projection of a simple cube with visible edges. Include the front, top, and side views on your sheet.

Answer: The student should produce three views: a front view showing a square face, a top view as a square, and a side view as a square, all aligned vertically and horizontally as per standard orthographic projection conventions.

Question 2: Sketch a rectangular box with a length of 80mm, width of 50mm, and height of 30mm. Show the front, top, and side views in proper alignment.

Answer: The student’s sketches should depict a rectangular prism with accurate dimensions: front view showing height and width, top view showing length and width, and side view showing length and height. All views should align correctly.

Question 3: Describe how an orthographic projection differs from a perspective drawing. Include at least two key differences.

Answer: Orthographic projection shows objects in multiple views with parallel lines and true dimensions, without foreshortening, whereas perspective drawing represents objects with converging lines, creating a sense of depth and distance.

Question 4: Label the following features on a sketch of a simple chair: seat, backrest, legs, and armrests. Assume a standard side view of the chair.

Answer: The sketch should clearly show the seat as a horizontal rectangle, the backrest as a vertical rectangle at the rear of the seat, four legs at each corner, and armrests extending from the backrest to the front of the seat.

Question 5: Draw a side view of a cylindrical can with a diameter of 60mm and a height of 120mm. Include hidden lines to show the top of the can.

Answer: The student should sketch a vertical rectangle representing the side profile of the can, with a horizontal ellipse at the top to indicate the circular opening, and use dashed lines to show hidden features if necessary.

Question 6: Explain why it is important to keep the views in orthographic projection aligned properly on the drawing sheet.

Answer: Aligned views ensure that features correspond correctly across different views, making it easier to interpret dimensions and shape, and maintaining consistency in the drawing.

Question 7: Draw the top view of an L-shaped object, where each arm of the L measures 50mm in length and 20mm in width.

Answer: The student should produce a sketch showing a large rectangle divided into two arms, each measuring 50mm by 20mm, joined at a right angle, aligned properly on the sheet.

Question 8: Identify and describe three common problems that can occur when creating orthographic drawings.

Answer: Problems include inconsistent line thickness, misalignment of views, and incorrect or missing dimensions. These issues can lead to confusion and misinterpretation of the drawing.

Question 9: Sketch a simple gear wheel with 12 teeth, a diameter of 80mm, and a central hole of 20mm diameter. Show the gear in a top view.

Answer: The student should draw a large circle with 12 evenly spaced teeth around the perimeter, a smaller central circle representing the hole, and details to indicate the gear teeth's shape.

Question 10: What is the purpose of using hidden lines in orthographic drawings? Provide an example of when they are necessary.

Answer: Hidden lines are used to show features that are not visible from the current view, such as internal holes or internal edges, for example, the inside of a hollow box or a drilled hole.