# Design of Machine Tool Gear Boxes - Mechanical Engineering (MCQ) questions and answers

1)   What is the purpose of using a gear box?

a. To increase torque
b. To increase speed
c. Converts single input speed into multiple output speeds
d. All of the above
 Answer  Explanation ANSWER: All of the above Explanation: No explanation is available for this question!

2)   A machine tool has minimum speed of 100 r.p.m. How many speed steps are required by it to achieve speed of 200 rpm? (Geometric progression ratio = 1.06)

a. 11
b. 12
c. 13
d. 14
 Answer  Explanation ANSWER: 12 Explanation: No explanation is available for this question!

3)   Maximum and minimum diameter of a shaft to be machined is 100 mm and 80 mm respectively. What is the maximum spindle speed if cutting velocity is 40 m/min?

a. 120 r.p.m
b. 127 r.p.m
c. 160 r.p.m.
d. 636 r.p.m.
 Answer  Explanation ANSWER: 160 r.p.m. Explanation: No explanation is available for this question!

4)   What is the maximum percentage loss of economic cutting speed if geometric progression ratio = 1.06 ?

a. 17.0 %
b. 11.5 %
c. 5.7 %
d. 2.9 %
 Answer  Explanation ANSWER: 2.9 % Explanation: No explanation is available for this question!

5)   Diameter range is high in geometric progression due to _________ spindle speed.

a. low
b. high
c. constant
d. none of the above
 Answer  Explanation ANSWER: low Explanation: No explanation is available for this question!

6)   What is harmonic progression?

a. Difference between reciprocal of two successive spindle speeds is constant
b. Difference between two successive spindle speeds is constant
c. Ratio of two successive spindle speeds is constant.
d. Ratio of two successive spindle speeds is variable.
 Answer  Explanation ANSWER: Difference between reciprocal of two successive spindle speeds is constant Explanation: No explanation is available for this question!

7)   Ratio of two spindle speeds is constant in _________ progression.

a. Arithmetic
b. Geometric
c. Harmonic
d. None of the above
 Answer  Explanation ANSWER: Geometric Explanation: No explanation is available for this question!

8)   Which of the following statements is true for structure/speed diagrams?

a. Structure diagrams gives range ratio of spindle speeds
b. Speed diagrams do not give range ratio of spindle speeds
c. Speed diagrams consider motor speed
d. All of the above
 Answer  Explanation ANSWER: Speed diagrams consider motor speed Explanation: No explanation is available for this question!

9)   Economic cutting speed is minimum if geometric ratio is _________

a. minimum
b. maximum
c. equal to economic cutting speed
d. none of the above
 Answer  Explanation ANSWER: minimum Explanation: No explanation is available for this question!

10)   What is the geometric progression ratio if maximum and minimum spindle speeds are 500 r.p.m and 300 r.p.m respectively? (Number of speed steps = 7)

a. 0.91
b. 1.5
c. 1.08
d. 2.0
 Answer  Explanation ANSWER: 1.08 Explanation: No explanation is available for this question!