Why does it echo in an empty room?

Related questions

1. Why do we hear echo?
2. Why do we hear more clearly in a furnished room than in an empty room?
3. Why we Cannot hear echo in a small room?
4. What is reverb time?
5. Is echo and reverb the same thing?
6. Whats the difference between echo and delay?
7. What causes an echo in a room?
8. What does an echocardiogram show that an ECG does not?
9. What is the reverb effect?
10. Why do we hear an echo when we speak loudly among hills?

Tags

1. #unable
2. #space
3. #level
4. #louder
5. #control
6. #furnished
7. #reflect
8. #filled
9. #while
10. #sound
11. #waves
12. #empty
13. #therefore
14. #because
15. #hence
16. #absorb
17. #furnishings
18. #convert
19. #better
20. #there
21. #echoes