Answer:

Explanation:
Use Doppler effect equation:
The Doppler effect is a physical phenomenon where an apparent change in wave frequency is presented by a sound source with respect to its observer when that same source is in motion. The general equation is given by:

- When the observer moves towards the source
is positive.
- When the observer moves away from the source
is negative.
- When the source moves towards the observer
is negative.
- When the source moves away from the observer
is positive.
Since the problem don't give us aditional information let's assume:

Which is the speed of sound in air.
And using the information provided by the problem:


The frequency perceived by the person is 331.046Hz
<em><u>Translation:</u></em>
<em><u></u></em>
Usa la ecuación del Efecto Doppler:
El efecto Doppler es un fenómeno físico en el que una fuente de sonido presenta un cambio aparente en la frecuencia de onda con respecto a su observador cuando esa misma fuente está en movimiento. La ecuación general viene dada por:

- Cuando el observador se mueve hacia la fuente
es positivo.
- Cuando el observador se aleja de la fuente es
negativo.
- Cuando la fuente se mueve hacia el observador
es negativa.
- Cuando la fuente se aleja del observador
es positiva.
Como el problema no nos da información adicional, supongamos que:

La cuál es la velocidad del sonido en el aire.
Y utilizando la información proporcionada por el problema:

La frecuencia percibida por la persona es 331.046Hz
Answer:
The focal length of the appropriate corrective lens is 35.71 cm.
The power of the appropriate corrective lens is 0.028 D.
Explanation:
The expression for the lens formula is as follows;

Here, f is the focal length, u is the object distance and v is the image distance.
It is given in the problem that the given lens is corrective lens. Then, it will form an upright and virtual image at the near point of person's eye. The near point of a person's eye is 71.4 cm. To see objects clearly at a distance of 24.0 cm, the corrective lens is used.
Put v= -71.4 cm and u= 24.0 cm in the above expression.


f= 35.71 cm
Therefore, the focal length of the corrective lens is 35.71 cm.
The expression for the power of the lens is as follows;

Here, p is the power of the lens.
Put f= 35.71 cm.

p=0.028 D
Therefore, the power of the corrective lens is 0.028 D.
Question; what causes earthquakes?
Answer; what causes earthquakes are mainly when rocks are underground and then suddenly break along a fault.
Answer:
Explanation:
Givens
vi = 10 m/s
a = 1.5 m/s^2
d = 600 m
vf = ?
Formula
vf^2 = vi^2 + 2*a*d
Solution
vf^2 = 10^2 + 2*1.5 * 600
vf^2 = 100 + 1800
vf^2 = 1900
sqrt(vf^2) = sqrt(1900)
vf = 43.59 m/s