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2 years ago

7

An ultrasound pulse used in medical imaging has a frequency of 5 MHz and a pulse width of 0.5 us. Ap- proximately how many osci

llations of the sound wave occur in the pulse? The number of oscillations is sometimes called the quality, Q, of the pulse. A pulse with little damping has Q 1, whereas a heavily damped pulse has e 1. Is the ultrasound pulse heavily damped?

1 answer:

podryga [215]2 years ago

4 0

At the frequency of 5 MHz, the period of the oscillations is 1/5meg. That's a period of 1/5 microsecond.

There are 5 full cycles in one full microsecond, and there are 2.5 full cycles in a 0.5 us pulse.

You'll have to decide for yourself how damped a pulse of 2.5 cycles is, because the parameters of the definition are corrupted in the question.

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True or false:slow movements of mantle rock called radiation transfer heat in the mantle.

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The best answer between the two options would be the second choice B) FALSE.

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3 years ago

The figure shows a 100-kg block being released from rest from a height of 1.0 m. It then takes it 0.90 s to reach the floor. Wha

Anna007 [38]

Answer:

The mass of the another block is 60 kg.

Explanation:

Given that,

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We need to calculate the acceleration of each block

Using equation of motion

$s=ut+\dfrac{1}{2}at^2$

Put the value into the formula

$1.0=0+\dfrac{1}{2}\times a\times(0.90)^2$

$a=\dfrac{2\times1.0}{(0.90)^2}$

$a=2.46\ m/s^2$

We need to calculate the mass of the other block

Using newton's second law

The net force of the block M

$Ma=Mg-T$

$T=Mg-Ma$ ....(I)

The net force of the block m

$ma=T-mg$

Put the value of T from equation (I)

$ma=Mg-Ma-mg$

$m(a+g)=M(g-a)$

$m=\dfrac{M(g-a)}{(a+g)}$

Put the value into the formula

$m=\dfrac{100(9.8-2.46)}{2.46+9.8}$

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2 years ago

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Dmitriy789 [7]

Answer:

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Explanation:

Given:

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- We know that the relation between angular speed w and time period T of an orbit is related by:

T = 2*p / w

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Hence, T = 92.8 min

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2 years ago

Calculate the speed of a proton after it accelerates from rest through a potential difference of 350 V.

AVprozaik [17]

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To read more about the conservation of energy, please go to brainly.com/question/14668053

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1 year ago

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Serggg [28]

Answer:

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2 years ago