science
Grade6
Easy
Question
The angle which the mirrors in a periscope make with the horizontal is ___ degrees.
- 30
- 45
- 60
- 90
Hint:
The two mirrors are parallel to each other but at an angle.
The correct answer is: 45
- A periscope, an optical instrument used in land and sea warfare, submarine navigation, etc., allows observers to hide behind objects, hide behind armor, or see their surroundings while underwater
- The simplest type of periscope consists of a tube, at the end of which there are two mirrors placed parallel to each other, but at an angle of 45° to the axis of the tube. This device does not produce magnification and does not provide cross-line images. Viewing angles are limited by the tube's simple geometry.
Whether the tube is long or narrow, the field of view is narrow.
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