R Ram Sharma 🎓 Coach ⭐ 193.88K Points 📊 Physics Q. What Elmer A. Sperry invented? (A) Hydraulic turbine (B) Gyrocompass (C) Hydroplane (D) Magnetic compass 👁️ Show Answer 🔗 Share ⚡Menu ✅ Correct Answer: (B) Gyrocompass You must be Logged in to update hint/solution 💬 Discussion 💬 Comment