Friction is caused by two solids rubbing together quickly.
Answer:
Air pollution---> smog
Water pollution---> eutrophication
Land pollution---> contaminated soil
Light pollution---> sky glow
Y: Radio
Z: Gamma
because gamma has a higher frequency then radio, therefore the higher the frequency the shorter the wavelength
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Answer:
The diameter of the needle is <u>4.675 cm</u>.
Explanation:
Given:
Volume flow rate is, 
Velocity of air expelled by pump is, 
Let the area of the needle be 'A' cm² and the diameter be 'd' cm.
We know that, volume flow rate of the air expelled by pump is given as the product of the needle's area and velocity of air flowing through that area.
Therefore, volume flow rate is given as:
Now, considering the needle to be circular, area of the needle can be written as:
Therefore, the diameter of the needle is 4.675 cm.
