GATE ME 2020 Set 2 — Question 39
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.MCQ+2 / -0.67MediumSimple, Compound & Epicyclic TrainsCams, Gears & Gear TrainsTheory of Machines & Vibrations
Theory of Machines & Vibrations → Cams, Gears & Gear Trains → Simple, Compound & Epicyclic Trains
Last updated
Question
The sun (S) and the planet (P) of an epicyclic gear train shown in the figure have identical number of teeth. If the sun (S) and the outer ring (R) gears are rotated in the same direction with angular speed and , respectively, then the angular speed of the arm AB is
Correct answer
(A) (3)/(4) ω_R + (1)/(4) ω_S
Solution
Let , , and be the number of teeth on the sun, planet, and ring gears respectively. Given . From the geometry of the gear train, the radius of the ring gear is . Since the number of teeth is proportional to the radius for gears with the same module, .
Using the relative velocity method for epicyclic gear trains:(The negative sign indicates that relative to the arm, the sun and ring gears rotate in opposite directions).This matches option (A).
Using the relative velocity method for epicyclic gear trains:(The negative sign indicates that relative to the arm, the sun and ring gears rotate in opposite directions).This matches option (A).
Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE ME question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Cams, Gears & Gear Trains
2026 Set 1 Q17A gear train with five gears is shown in the figure below. The number of teeth on each gear is…2026 Set 1 Q18In a single degree of freedom vibrating system with only viscous damping, the critical damping…2026 Set 1 Q20The rotor of an aeroplane engine has a mass moment of inertia . The engine…2026 Set 1 Q22Worm gearsets are used for transmitting rotary motion between2026 Set 1 Q42A 5 kg mass is suspended at the free end of an overhanging massless beam, having a pin support and…