Gravity is measured with an instrument called a Gravimeter. Gravity is expressed using a special unit called a Newton. Although both of these answers would be technically correct, I believe the answer to this question is Newtons.
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
In an open system such as a campfire, matter can lose particles, gain particles or exchange particles.
Answer
D.Diffraction
Explanation
Diffraction is a property that is experienced by waves when they come across a barrier when they are in motion.
The ways tends to curve behind the barrier. This is called diffraction of waves.
Now, sound is a wave and it also experience diffraction. . So the brother will be able to hear the sound due to diffraction