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:
22%
Explanation:
55 - 45 = 10
10/45 simplifies to 2/9
2/9 = 0.22222... so 22.22% (rounded 22%)
Explanation:
Given that,
Displacement in ice block, 
Force exerted by water, 
To find,
Work done by the force during the displacement.
Solve,
We know that the product of force and displacement is called work done. It is also equal to the dot product of force and displacement as :


We know that, i.i = j.j = k.k = 1

So, the work done by the force on the block during the displacement is 4181 Joules.
Answer:
Yep.. It's balanced and its a combination reaction
Explanation:
Reactants : S₈ + 24F₂
Product 8SF₆
Here we can use the work energy theorem

here we know that

as it come to rest finally



now work done by friction force will be given as


Work done by spring force is given as



so now plug in all data above


so above is the friction coefficient