Topic: Machine Design
Which one of the following is trapezoidal thread?
- A. Acme
- B. Square
- C. Buttress
- D. All of the above
Answer: A. Acme
Explanation: Acme thread is heavily utilized for power transmission (e.g., lead screws). It is virtually identical to a standard trapezoidal thread in its characteristics and applications, with the primary difference being its thread angle of 29° instead of 30°.