<u>Answer:</u>
Submarines use a device called Periscope that uses the concept of multiple reflections and help us see objects above the water surface.
<u>Explanation:</u>
When a light ray falls on a reflecting surface like a mirror, it gets reflected. In multiple reflections, the incident light ray is made to reflect multiple times by arranging the reflecting surfaces in different ways.
In submarines, we use Periscope, which is a long tube like structure. The long tube is bent at ends. It uses two simple mirrors which are placed parallel to each other at an angle of 45 degrees. The light from one mirror gets reflected to the other mirror, thus causing a multiple reflection.
Answer:
The glass rod remains charged due to electrification by the silk
Compressions are the areas of high pressure while rarefractions are low pressure area
Answer:
The boat won't be able to move if the oars were out and there was no thruster. If there was a flow of the water then yes there would be a moving boat.
Answer:
The power of top half of the lens is 0.55 Diopters.
Explanation:
Since, the person can see an object at a distance between 34 cm and 180 cm away from his eyes. Therefore, 180 cm must be the focal length of the upper part of lens, as the top half of the lens is used to see the distant objects.
The general formula for power of a lens is:
Power = 1/Focal Length in meters
Therefore, for the top half of the lens:
Power = 1/1.8 m
<u>Power = 0.55 Diopters</u>
