Explanation

Sonar stands for "Sound Navigation and Ranging."

It uses high-frequency sound waves (ultrasonic waves) to detect and locate objects underwater

Explanation

In a photographic camera fitted with a convex lens, a real and inverted image is formed on the film. 

Convex lenses (also called converging lenses) always form real and inverted images when the object is placed beyond the focal point.

In a camera, the object (the scene being photographed) is positioned beyond the lens's focal point,

Ensuring that the light rays converge to form a real, inverted image on the film. 

Explanation

AMPS is based on the initial electromagnetic radiation spectrum allocation by the Federal Communications Commission (FCC) in 1970.

it was officially introduced in the Americas on October 13, 1983

AMPS was deployed in many other countries:

1. including Israel in 1986,
2. Australia in 1987,
3. Singapore in 1988,
4. and Pakistan in 1990

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ND04-12-2022

Explanation

• Weber is the SI unit of magnetic flux.
• 
  
• ***
• DETAIL:
• Unit system--->     SI
  
• Unit of------->             magnetic flux
• Symbol------->             Wb
• Named after-------->    Wilhelm Eduard Weber
• 1 Wb in ... ...         is equal to ...
  
• SI base units----->    1 kg⋅m2⋅s−2⋅A−1
• Gaussian units----->  1×108 Mx

Explanation

• A lake starts freezing because of the cold atmosphere. It will first freeze At the top surface
• ***
• concept:
• when the water freezes to ice, the ice becomes significantly less dense than the water and continues to float on the lake's surface.
• Below 4° Celsius, water becomes less dense as it gets colder, causing water to freeze to float to the top.
  
  

Explanation

The phenomenon of refraction of light is the shift in the path of light as it travels from one medium to another

Explanation

The guitar is a musical instrument of the chordophone family.

The standard guitar has following six strings:

1. E

2. A

3. D

4. G

5. B

6. E

Explanation

A galvanometer is an instrument that can detect and measure small amounts of current in an electrical circuit

Explanation

• Photovoltaic (PV) cells convert solar energy into electricity through a physical and chemical phenomenon known as the photovoltaic effect.
• Photovoltaic cells are also called solar cells.
• They convert light energy from the Sun directly into electrical energy.

Explanation

• The great red Spot is a hurricane in Jupiter's southern hemisphere with purple-colored clouds that spin counterclockwise at wind speeds that exceed those in any hurricane on the earth.
• The excellent purple Spot has slowly changed over time, and is presently about 1.3 instances as huge as our planet.