Answer:
A police car with its siren on is driving towards you, and you perceive the pitch of the siren to increase.
Explanation:
In Physics, Doppler effect can be defined as the change in frequency of a wave with respect to an observer in motion and moving relative to the source of the wave.
Simply stated, Doppler effect is the change in wave frequency as a result of the relative motion existing between a wave source and its observer.
The term "Doppler effect" was named after an Austrian mathematician and physicist known as Christian Johann Doppler while studying the starlight in relation to the movement of stars.
<em>The phenomenon of Doppler effects is generally applicable to both sound and light. </em>
An example of the Doppler effect is a police car with its siren on is driving towards you, and you perceive the pitch of the siren to increase. This is so because when a sound object moves towards you, its sound waves frequency increases, thereby causing a higher pitch. However, if the sound object is moving away from the observer, it's sound waves frequency decreases and thus resulting in a lower pitch.
<em>Other fields were the Doppler effects are applied are; astronomy, flow management, vibration measurement, radars, satellite communications etc. </em>
The north vectors add up as so the south vectors. Then subtract the two. For north its 4 + 5 = 9. South is 2 + 5 = 7. Then 9-7 = 2km North (D)
Increase .... decrease .... presumably it's the "best shape" for a body which has been formed by the gravitational force
Answer:
The density of one halves 11.3 g / cm cube
Explanation:
Density remain same because cutting the bar in half , mass and volume will decrease to half so density will not change .
density = 
In salty water ions are produced by the salt
here salt is NaCl
so it will break in Na⁺ and Cl⁻
They carry the current
Na⁺ moves towards cathode and Cl⁻ moves towards anode
So current is carrying by ions which are Na⁺ and Cl⁻
