Which two statements describe how ultrasound technology produces an
image of part of the body?
A. The amount of time it takes for a wave to return can be used to
create an image.
B. Low-frequency sound waves are reflected by tissues in the body.
C. High-frequency sound waves are reflected by tissues in the body.
D. Body tissues absorb high-frequency sound waves, producing an
image

Answer:

  T₀ = 2π [tex]\sqrt{\frac{m}{k} }[/tex]           T = [tex]\sqrt{\frac{5}{6} }[/tex] T₀

Explanation:

When the block is oscillating it forms a simple harmonic motion, which in the case of a spring and a mass has an angular velocity

        w = [tex]\sqrt{k/m}[/tex]

To apply this formula to our case, let's look for the equivalent constant of the springs.

Let's start with the springs in parallels.

* the three springs in the upper part, when stretched, lengthen the same distance, therefore the total force is

       F_total = F₁ + F₂ + F₃

the springs fulfill Hooke's law and indicate that the spring constant is the same for all three,

       F_total = - k x - k x - kx = -3k x

therefore the equivalent constant for the combination of the springs at the top is

      k₁ = 3 k

* the two springs at the bottom

following the same reasoning the force at the bottom is

        F_total2 = - 2 k x

the equivalent constant at the bottom is

         k₂ = 2 k

now let's work the two springs are equivalent that are in series

the top spring is stretched by an amount x₁ and the bottom spring is stretched x₂

            x₂ = x -x₁

            x₂ + x₁ = x

if we consider that the springs have no masses we can use Hooke's law

            [tex]-\frac{F_{1} }{k_{1} } - \frac{F_{2}}{k_{2} } = \frac{F}{k_{eq} }[/tex]

therefore the equivalent constant is the series combination is

             [tex]\frac{1}{k_{eq} } = \frac{1}{k_{1} } + \frac{1}{k_{2} }[/tex]

we substitute the values

             \frac{1}{k_{eq} }  = \frac{1}{3k } + \frac{1}{2k }  

             \frac{1}{k_{eq} }  = \frac{5}{6k} }  

              k_eq = [tex]\frac{6k}{5}[/tex]  

therefore the angular velocity is

             w = [tex]\sqrt{\frac{6k}{5m} }[/tex]  

angular velocity, frequency, and period are related

           w = 2π f = 2π / T

           T = 2π / w

            T = 2π [tex]\sqrt{\frac{5m}{6k} }[/tex]

           T₀ = 2π [tex]\sqrt{\frac{m}{k} }[/tex]

           T = [tex]\sqrt{\frac{5}{6} }[/tex] T₀

Answer:

Ocean currents act as conveyer belts of warm and cold water, sending heat toward the polar regions and helping tropical areas cool off, thus influencing both weather and climate.

Explanation:

Answer:

I actually have 20000 arena points thank you very much

Answer: Caca means in French lol.

Answer:

=101343.62N/m^2

Explanation:

absolute pressure on the bottom of a swimming pool= atmospheric pressure +( 2 ×ρ ×g)

( 2 ×ρ ×g)= guage pressure

atmospheric pressure= 101325pa

h= height= 1.9 mm = 1.9×10^-3m

ρ = density of water

= 1000kg/m^3

g= acceleration due to gravity= 9.8m/s^2

Then substitute, we have

absolute pressure on the bottom of a swimming pool= 101325+ [0.0019 ×1000 × 9.8)]

=101343.62N/m^2

Hence, the absolute pressure on the bottom of a swimming pool is =101343.62N/m^2

Answer:

both

Explanation:

Answer:

7. d. England during the Age of Enlightenment

8. a. State governments do not usually act together

Explanation:

The Age of Enlightenment occurred in the 18th century and at this time England was a Constitutional monarchy with a monarch and parliament ruling the country with different powers.

The third and fourth methods of amending the Constitution will be much harder to use because state governments simply do not usually act together as they most times have ideological differences. The sheer number of states it would take to unite for these methods to be used makes this impractical.

Answer: B) Methyl alcohol requires less than half as much energy per kg to evaporate than water does

Explanation:

Latent heat of vaporization is the amount of heat required to convert 1 kilo gram of liquid into its vapor state without change in its temperature.

Heat of vaporization is more for water than for methyl alcohol which means more heat is required to convert from liquid to vapour form.

As the Heat of vaporization for methyl alcohol  (1100) is almost half as that of Heat of vaporization for water (2257) , it means  Methyl alcohol requires less than half as much energy per kg to evaporate than water does.

Answer:

False

Explanation:

A contact force is any force that requires contact to occur. Contact forces are ubiquitous and are responsible for most visible interactions between macroscopic collections of matter. Pushing a car up a hill or kicking a ball across a room are some of the everyday examples where contact forces are at work. 

Answer:

false

Explanation:

Answer:

true

Explanation:

I believe the answer i chose because the earths atmosphere is mostly made up of different things that causes the earth to interact with human life and also interacts with what's in the atmosphere like energy oxygen carbon dioxide and all the stuff like that i hope its right.

Answer:

Electric field will be greater when the battery is connected by the factor of 2.

Explanation:

Solution:

I will be doing some algebraic calculations to answer this question:

As we know that,

Q = CV

and

C = [tex]\frac{AE_{0} }{d}[/tex]

So, when separation = d/2, then,

[tex]C^{'}[/tex] = [tex]\frac{AE_{0} }{d/2}[/tex] by rearranging we get

So,

[tex]C^{'}[/tex]  = 2C

We further know that, Voltage will remain same if the battery is  connected.

This further implies that,

Q = CV

So,

[tex]Q^{'}[/tex] = [tex]C^{'}[/tex]V

[tex]Q^{'}[/tex]  = 2CV

[tex]Q^{'}[/tex] = 2Q

and we also know that,

Electric field E = [tex]\frac{Q}{AE_{0} }[/tex]

So, the new E or [tex]E^{'}[/tex] = [tex]\frac{Q^{'} }{AE_{0} }[/tex]

Hence,

[tex]E^{'}[/tex] = [tex]\frac{2Q}{AE_{0} }[/tex] = 2E

[tex]E^{'}[/tex] = 2E

when battery is disconnected, Q remain the same.

So,

When disconnected

E = E

E = [tex]\frac{Q}{AE_{0} }[/tex]  = Same

Hence, we can see that the magnitude of the electric does not depend upon the distance of separation. Instead it does depend upon the magnitude of charge.

So, when battery is disconnected, Q is same, so the Electric field.

But when it is connected, [tex]Q^{'}[/tex] = 2Q and the [tex]E^{'}[/tex] = 2E

So,

[tex]\frac{E connected}{E disconnected} = \frac{E^{'} }{E}[/tex] = [tex]\frac{2E}{E}[/tex] = 2

Electric field will be greater when the battery is connected by the factor of 2.

Answer:

option (a)

Explanation:

Maintaining distance while driving in traffic can avoid the chances of an accident.                        

When the driver is behind you is trying to pass you to avoid the collision you should maintain a distance greater than 3 sec.

Hence, option (a) is correct.

Answer:

a driver behind your vehicle is trying to pass you

Explanation:

took test and checked

Answer:

t = 3/8 seconds

Explanation:

h=-16t^2 - 10t+6

h= 0 when it hits the ground

0=-16t^2 - 10t+6

factor out a -2

0= -2(8t^2 +5t -3)

divide by -2

0 = (8t^2 +5t -3)

factor

0=(8t-3) (t+1)

using the zero product property

8t-3 = 0    t+1 =0

8t = 3         t= -1

t = 3/8     t= -1

t cannot be negative  ( no negative time)

t = 3/8 seconds

Answer:

There are many kinds of waves all around us. There are waves in the ocean and in lakes. Did you also know that there are also waves in the air? Sound travels through the air in waves and light is made up of waves of electromagnetic energy.

The wavelength of a wave describes how long the wave is. The distance from the "crest" (top) of one wave to the crest of the next wave is the wavelength. Alternately, we can measure from the "trough" (bottom) of one wave to the trough of the next wave and get the same value for the wavelength.

The frequency of a wave is inversely proportional to its wavelength. That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength.

Light waves have very, very short wavelengths. Red light waves have wavelengths around 700 nanometers (nm), while blue and purple light have even shorter waves with wavelengths around 400 or 500 nm. Some radio waves, another type of electromagnetic radiation, have much longer waves than light, with wavelengths ranging from millimeters to kilometers.

Sound waves traveling through air have wavelengths from millimeters to meters. Low-pitch bass notes that humans can barely hear have huge wavelengths around 17 meters and frequencies around 20 hertz (Hz). Extremely high-pitched sounds that are on the other edge of the range that humans can hear have smaller wavelengths around 17 mm and frequencies around 20 kHz (kilohertz, or thousands of Hertz).

Explanation:

Explanation:

Hope This Helped U

Brqinliest

Answer:True

Explanation:

Answer:

I am going to say true not too sure

Answer:

VAB = 20km/hr

Explanation:

Given the following data;

Velocity of car A, VA = 60km/hr

Velocity of car B, VB = 80km/hr

To find the relative velocity of B w.r.t A, VAB;

Since the two cars are moving in the same direction, we have;

VAB = VB - VA

Substituting into the equation, we have;

VAB = 80 - 60

VAB = 20km/hr

Therefore, the relative velocity of car B with respect to car A is 20 kilometers per hour.

Answer and Explanation:

The computation is shown below:

As we know that

Frequency = Speed ÷ wavelength

= (3 × 10^8 )÷ (632.8 × 10^-9)

= 4.74 × 10^14 Hz

Speed in flourite is

= Vaccum speed ÷ refraction index

= 3 × 10^8 ÷ 1.434

= 2.092 × 10^8 m/s

wavelength is

= Speed in flourite ÷ frequency

= (3 × 10^8 × 632.8 × 10^-9) ÷ (1.434 × 3 × 10^8)

= 441.28nm

Answer:

Explanation:

The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them. This means that the force of gravity increases with mass, but decreases with increasing distance between objects

so a option is correct

Answer: kinetic energy decreases

Explanation:

When the angle between the net force and the displacement of an

object is greater than 90 degree, the Kinetic energy decreases.

The work done by a net force in moving an object over a given distance is given as;

[tex]W = F \times d \ cos(\theta)[/tex]

where;

The value of cos(θ) decreases from 0 to 180, consequently, the value of work-done will decrease as well.

Based on work-energy theorem, the work done on the object is equal to kinetic energy of the object.

[tex]W = K.E[/tex]

Thus, we can conclude that when the angle increases, the Kinetic energy decreases.

Learn more about kinetic energy here:https://brainly.com/question/10063455

The efficiency of the leaf blow is 48%.

         Here, E = Energy transferred

                   m = Mass

                   Ф = Temperature change

            Here, E = Energy transferred

                      P = Power

                      t = time

        Here, v = speed

                   f = frequency

                  ∧ = wavelength

       Efficiency =  (Useful power out / Total power in ) = 360/750 = 0.48

So, the efficiency of the leaf blower is 48%.

To learn more about efficiency, refer to: https://brainly.com/question/21305967

#SPJ2

Answer:

oil heats faster

Explanation:

that's all

Answer:

Oil gets hotter faster or something

Answer:

0.47m3

Explanation:

Volume = Mass / Density

In this case:

Mass - 1280 kg

Density - 2700kg/m3

1280 / 2700 = 0.4740741m3

When this is rounded off ( 2 d.p ):

0.47 m3

HOPE THIS HELPED

sowwie :( i need points

Explanation:

Answer:

[tex]\huge\boxed{\sf P.E. = 39.2\ Joules}[/tex]

Explanation:

Given Data:

Mass = m = 4 kg

Acceleration due to gravity = g = 9.8 m/s²

Height = h = 1 m

Required:

Potential Energy = P.E. = ?

Formula:

P.E. = mgh

Solution:

P.E. = (4)(9.8)(1)

P.E. = 39.2 Joules

[tex]\rule[225]{225}{2}[/tex]

Hope this helped!

Answer:

True. Diffusion and osmosis are forms of passive transport.

Explanation:

In diffusion, particles move from an area of higher concentration to one of lower concentration until equilibrium is reached.

In osmosis, a semipermeable membrane is present, so only the solvent molecules are free to move to equalize concentration.

Answer:

100% true

Explanation:

Simple diffusion and osmosis are both forms of passive transport and require none of the cell's ATP energy. Example of diffusion: Gas Exchange A biological example of diffusion is the gas exchange that occurs during respiration within the human body.

The space station completes 2 revolutions each minute, so that it traverses a distance of 2π (100 m) = 200π m each minute, giving it a linear/tangential speed of

v = (200π m) / (60 s) ≈ 10.472 m/s

(a) The astronaut would experience an acceleration of

a = v ² / (100 m) ≈ 1.09662 m/s² ≈ 0.1119g ≈ 0.11g

(b) Now you want to find the period T such that a = g. This would mean the astronaut has a tangential speed of

v = (200π m) / T

so that her centripetal/radial acceleration would match g :

a = g = ((200π m) / T )² / (100 m)

Solve for T :

(100 m) g = (400π ² m²) / T ²

T ² = (400π ² m²) / ((100 m) g) = (4π ² m)/g

T = √((4π ² m) / (9.8 m/s²)) ≈ 2π √(0.102 s²) ≈ 2.007 s ≈ 2.0 s

Answer:

210 ft.

Explanation:

Since a square has 4 sides and all sides are equal, just do 210 divided by 4.

Answer:

5 metres

Explanation:

Work Done = Force x Distance

So Distance = Work done ÷ Force

= 35 ÷ 7.0

= 5 metres

Answer:

100kgms⁻¹

Explanation:

Given parameters:

Mass of the sled  = 20kg

Velocity of the sled  = 5m/s

Unknown:

Momentum of the sled = ?

Solution:

The momentum of a body is the quantity of motion such a body possesses. Due to this;

    Momentum  = mass x velocity

Now insert the parameters and solve;

      Momentum  = 20 x 5  = 100kgms⁻¹

Answer:

Here you go, hope this helps! :)

Explanation:

Opportunity cost is the value of the next best thing you give up whenever you make a decision. It is "the loss of potential gain from other alternatives when one alternative is chosen". ... For example, opportunity cost is how much leisure time we give up to work.