science
Grade6
Easy
Question
A ____ is an optical device that helps us to see over the top of an obstacle.
- Mirror
- Telescope
- Periscope
- Kaleidoscope
Hint:
A periscope is an optical device that helps us to see over the top of an obstacle.
The correct answer is: Periscope
- A periscope, an optical instrument used in land and sea warfare, submarine navigation, etc., allows the observer to hide behind objects, hide behind armor, or see their surroundings while underwater.
- The periscope contains two mirrors or reflecting prisms to redirect light coming from the scene being observed.
- The first deflects downward through a vertical tube and the second deflect horizontally for comfortable viewing of the scene.
Related Questions to study
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What should a person do when dust enters their eyes?
The correct option is c)Wash your eyes using clean water.
Slight temporary visual impairment may occur. Once the dust is removed, the swelling and irritation of the eye is reduced and vision returns to normal. However, there is a possibility of infection due to bacteria contained in dust. Therefore we should immediately wash your eyes with cold water.
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The correct option is c)Wash your eyes using clean water.
Slight temporary visual impairment may occur. Once the dust is removed, the swelling and irritation of the eye is reduced and vision returns to normal. However, there is a possibility of infection due to bacteria contained in dust. Therefore we should immediately wash your eyes with cold water.
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The least distance of distinct vision of a human eye is ___ cm.
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An object is perceived to be moving when its images appear at the rate of ___ images per second.
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A normal human eye cannot see the object placed at a distance ____ from itself.
A normal human eye cannot see the object placed at a distance ____ from itself.
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What would happen to the size of the pupil when a person enters a well-lit room from a dark room?
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