Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = (
) · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f =
· 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
The EM spectrum has no limits. Any frequency you can imagine
is the frequency of some electromagnetic radiation somewhere.
Answer:
The correct answer is - Plantae.
Explanation:
Drosera m<em>agnifica</em> is discovered in 2015 for the first time and the characteristics this organism's cell shows are -
- permanent vacuoles
- surrounded by cellulose layer
Vacuoles are present in both Plantae and Animalia kingdom of the eukaryotic organism but in animal cells, there are small and numerous vacuoles present and they are not permanent whereas in plant cells vacuoles are present permanently.
The cell of an animal cell has no surrounding layer other than cell membrane while in the plant cell there is a supporting and protecting layer of cellulose cell wall present.
On the basis of the given characteristics, it is confirmed that the Drosera magnifica belongs to Plantae kingdom.
Part a.
u = 0, the initial velocity
v = 60 mi/h, the final velocity
a = 2.35 m/s², the acceleration.
Note that
1 m = 1609.34 m.
Therefore
v = (60 mi/h)*(1609.34 m/mi)*(1/3600 h/s) = 26.822 m/s
Use the formula
v = u + at
(26.822 m/s) = (2.35 m/s²)*(t s)
t = 26.822/2.35 = 11.4 s
Answer: 11.4 s
Part b.
We already determined that v = 60 mi/h = 26.822 m/s.
t = 0.6 s
Therefore
(26.822 m/s) = (a m/s²)*(0.6 s)
a = 26.822/0.6 = 44.7 m/s²
Answer: 44.7 m/s²