Ask question

Ask question

All categories

2 years ago

11

With each beat of your heart the aortic valve opens and closes. The valve opens and closes very rapidly, with a peak velocity as

high as 4 m/s. If we image it with 7 MHz sound and the speed of sound is approximately 1500 m/s in human tissue, what is the frequency shift between the opening and closing of the valve?

1 answer:

Nonamiya [84]2 years ago

4 0

Answer:

|Δf| = 37.3 kHz

Explanation:

given,

peak velocity = 4 m/s

speed of the sound = 1500 m/s

frequency = 7 MHz

$v = C\dfrac{\pm \dlta f}{2 f_0}$

$\delta f = \pm 2 f_0 (\dfrac{V}{C})$

$\delta f = \pm 2\times 7 (\dfrac{4}{1500})$

$=\pm 0.0373 MHz$

= 37.3 kHz

|Δf| = 37.3 kHz

hence, frequency shift between the opening and closing valve is 37.3 kHz

You might be interested in

If a football player hits the ball with a force of 50 N, determine the reaction force.

mel-nik [20]

Answer: 60

Explanation: if u hit it it will have impact and the impact added 10n

4 0

2 years ago

A kayakeris paddling 2.50 m/s at an angle of 45° (northeast) and the current is moving 1.25 m/s at an angle of 315° (southeast).

PIT_PIT [208]

The kayaker has velocity vector

<em>v</em> = (2.50 m/s) (cos(45º) <em>i</em> + sin(45º) <em>j</em> )

<em>v</em> ≈ (1.77 m/s) (<em>i</em> + <em>j</em> )

and the current has velocity vector

<em>w</em> = (1.25 m/s) (cos(315º) <em>i</em> + sin(315º) <em>j</em> )

<em>w</em> ≈ (0.884 m/s) (<em>i</em> - <em>j</em> )

The kayaker's total velocity is the sum of these:

<em>v</em> + <em>w</em> ≈ (2.65 m/s) <em>i</em> + (0.884 m/s) <em>j</em>

That is, the kayaker has a velocity of about ||<em>v</em> + <em>w</em>|| ≈ 2.80 m/s in a direction <em>θ</em> such that

tan(<em>θ</em>) = (0.884 m/s) / (2.65 m/s) → <em>θ</em> ≈ 18.4º

or about 18.4º north of east.

5 0

3 years ago

Describe in your own words what is meant by the statement that the Sun is in hydrostatic equilibrium.

Jet001 [13]

Answer and Explanation:

Hydrostatic equilibrium is the condition in which force is balance that is upward force and downward force the downward force is due to gravitational force and the upward force is due to the pressure. The Sun is said to be in hydrostatic equilibrium means the force acting on it is balance means upward force which is due to pressure is same as the force exerted by gravitation.

8 0

3 years ago

The secret recipe to the ever-popular veggie burgers in the college cafeteria is hidden in a drawer in the director’s office. Tw

djverab [1.8K]

Answer:

Waxing crescent to Waxing gibbous

Explanation:

As the Moon goes around Earth and Earth goes around the Sun, the Moon shows us different phases throughout this journey. Also because of peculiar revolution period around the Earth the rise and set time of Moon changes daily. New Moon rises with the Sun rise and sets with Sun set. Waxing half rises in the mid of the day and sets at midnight. Full Moon rises after sunset and sets at sunrise.

The suitable phases will be from waxing crescent to waxing gibbous. The phase of the Moon, 3 days before the full Moon can be selected as the Moon will set by around 2.5 hours before the Sun rise.

4 0

3 years ago

The orbital motion of Earth around the Sun leads to an observable parallax effect on the nearest stars. For each star listed, ca

Murrr4er [49]

Answer:

Following are the answer to this question:

Explanation:

Formula:

$D(PC) =\frac{1}{parallax}\\\\D(av)=D(PC) \times 20.626\ J$

Calculating point A:

when the value is $0.38$

$\to 0.38 \toD(PC)= \frac{1}{0.38}\\\\$

$=2.632$

$\to D(a.v) = \frac{1}{0.38} \times 206265\\$

$=542,802.6$

Calculating point B:

when the value is $0.75$

$\to D(PC)=\frac{1}{0.75}$

$=1.33$

$\to D(a.v) = \frac{1}{0.75} \times 206265\\$

$=275,020$

Calculating point C:

when the value is $0.28$

$\to D(PC)=\frac{1}{0.28}$

$=3.571$

$\to D(a.v) = \frac{1}{0.28} \times 206265\\$

$=736660.7$

Calculating point D:

when the value is $0.42$

$\to D(PC)=\frac{1}{0.42}$

$=2.38$

$\to D(a.v) = \frac{1}{0.42} \times 206265\\$

$=490910.7$

Calculating point E:

when the value is $0.31$

$\to D(PC)=\frac{1}{0.31}$

$=3.226$

$\to D(a.v) = \frac{1}{0.31} \times 206265\\$

$=665370.97$

6 0

2 years ago