Answer: I think Windows.
Explanation: The absorption of light makes an object dark or opaque to the wavelengths or colors of the incoming wave: Wood is opaque to visible light. Some materials are opaque to some wavelengths of light, but transparent to others. Glass and water are opaque to ultraviolet light, but transparent to visible light.
Answer:
the diameter of the nozzle = 3 cm
Explanation:
let the diameter of nozzle be x cm.
then, area of cross-section at nozzle =
nozzle with a speed of 20 m/s, and speed of the water at the faucet is 5 m/s.
area of cross section at faucet = = 9π
now , area×velocity has to be constant (since area×velocity gives volume flow rate which should be same at both ends).
therefore
5×9π = 20×π×x^2/4
=>45 = 5×x^2
=>9 = x^2
=> x = 3 cm (as 3^2 =9)
therefore, the diameter of the nozzle = 3 cm