This strange object was built on the coast of Great Britain. What is it?

sun clock
storm detector
acoustic mirror
emergency radio receiver
Prior to World War II and the in­ven­tion of radar, acoustic mirrors were built as early warning devices around the coasts of Great Britain, with the aim of de­tect­ing airborne in­va­sion­s. The de­vel­op­ment of radar put an end to further ex­per­i­men­ta­tion with the tech­nique.

Answers distribution

sun clock
storm detector
acoustic mirror
emergency radio receiver
answers
flagFinland
0%
0%
100%
0%
32
flagItaly
0%
2%
97%
0%
42
flagthe Netherlands
8%
4%
82%
4%
23
flagSpain
0%
11%
82%
5%
17
flagGermany
10%
2%
75%
10%
113
flagPoland
11%
6%
72%
9%
8362
flagNorway
20%
5%
70%
5%
20
flagthe United Kingdom
17%
7%
64%
9%
332
flagRepublic of Ireland
18%
9%
63%
9%
11
flagthe United States
15%
5%
61%
15%
167
flagCanada
7%
0%
61%
30%
13
flagLithuania
0%
14%
57%
28%
14
flagIndia
26%
19%
28%
25%
56

Gender

men77%
women74%
sun clock
6%
10%
storm detector
5%
6%
acoustic mirror
77%
74%
emergency radio receiver
9%
9%

Language versions

question
answers
results
flag
This strange object was built on the coast of Great Britain. What is it?
350
47%

Details

Author: globalquiz.org
Illustration: shirokazan
tools
Should this question be improved? Improve it.
Globalquiz questions are translated by users for other users. Translate this question.