To solve this problem we will apply the concepts related to the Doppler effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. Mathematically it can be described as,
Here,
= Frequency of Source
= Speed of sound
f = Frequency heard before slowing down
f' = Frequency heard after slowing down
v = Speed of the train before slowing down
So if the speed of the train after slowing down will be v/2, we can do a system equation of 2x2 at the two moments, then,
The first equation is,
Now the second expression will be,
Dividing the two expression we have,
Solving for v, we have,
Therefore the speed of the train before and after slowing down is 22.12m/s
Answer:
ac = 72 m/s²
Fc = 504 N
Explanation:
We can find the centripetal acceleration of the hammer by using the following formula:
where,
ac = centripetal acceleration = ?
v = constant speed = 12 m/s
r = radius = 2 m
Therefore,
<u>ac = 72 m/s²</u>
<u></u>
Now, the centripetal force applied by the athlete on the hammer will be:
<u>Fc = 504 N</u>
Answer:
Q = 5 L/s
Explanation:
To find the flow you use the following formula (para calcular el caudal usted utiliza la siguiente formula):
V: Volume (volumen) = 200L
t: time (tiempo) = 40 s
you replace the values of the parameters to calculate Q (usted reemplaza los valores de los parámteros V y t para calcular el caudal):
Hence, the flow is 5 L/s (por lo tanto, el caudal es de 5L/s)
Answer:
6480 km
Explanation:
The speed of the object is
v = 7500 cm/sec
We need to convert centimetres into kilometers and seconds into days. We have:
Using these conversion factors, we find:
