Orthographic Projection: Mechanical Drawing is one of 9 topics in the Grade 12 Engineering Graphics and Design CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. What is the purpose of a lock nut fitted against a standard nut on the same bolt?
To prevent the assembly from loosening under vibration
To increase the bolt's tensile strength
To replace the need for a washer entirely
To provide electrical insulation
Answer: To prevent the assembly from loosening under vibration — A lock nut is tightened against the first nut so the two jam against each other, resisting the tendency of a single nut to work loose over time under vibration.
Easy
2. What does a washer primarily do when placed under a nut or bolt head?
Distributes the clamping load over a wider area of the component surface
Transmits rotational torque between a shaft and a mounted component
Prevents welding of the joint
Cuts the thread on a bolt
Answer: Distributes the clamping load over a wider area of the component surface — A washer is a thin flat disc that distributes the clamping load over a wider surface area and protects the component surface from damage as the nut is tightened.
Medium
3. Name the precisely machined slots cut into both a shaft and a mounted hub, into which a key is fitted to transmit torque.
Answer: keyways — Keyways are precisely machined slots cut into both a shaft and a mounted component's hub, into which a key is fitted to transmit rotational torque.
