Hoover Dam on the Colorado River is the highest dam in the United States at 221 m, with an output of 1300 MW. The dam generates electricity with water taken from a depth of 100 m and an average flow rate of 640 m3/s
(a) Calculate the power in this flow in watts. 627200000XW Enter a number
(b) What is the ratio of this power to the facility's average of 680 MW? Additional Materials Reading

Answers

Answer 1

Answer:

a) 627840000 W

b) 0.9233

Explanation:

The rate at which energy flows through the dam for the generation of electricity is proportional to the volulme flow rate times the potential energy per unit volume.

Mathematically,

P = Q(ρgh)

Where, ρ is water density, g is accelaration due to gravity, h is height through which water falls over the turbine and Q is the discharge.

a) The power can be calculated as

P = 640(1000×9.81×221)

P = 627840000 W

b) The ratio = Calculated power / avarage power

= 62784×10^4/680×10^6

= 0.9233


Related Questions

The Moon is attracted to the Earth. The mass of the Earth is 6.0x1024 kg and the mass of the Moon is 7.4x1022 kg. If the Earth and Moon are 345,000 km apart, what is the gravitational force between them?

Answers

Sorry I don't know the answer

A 16.2-g bullet with an initial speed of 850 m/s embeds itself in a 40.0-kg block, which is attached to a horizontal spring with a force constant of 1000 N/m. What is the maximum compression of the spring

Answers

The maximum compression in the spring is 0.06883 meters.

Given to us,

mass of bullet, [tex]m= 16.2\ grams[/tex]

velocity of bullet, [tex]v= 850\ meter/second[/tex]

mass of the block, [tex]m_2= 40\ kilograms[/tex]

velocity of block, [tex]v_2= 0\ meter/second[/tex]

spring constant, [tex]k = 1000\ Newton/meter[/tex]

Combined mass after collision,

[tex]\begin{aligned}M&= m_1+m_2\\&= 40.0162\ Kilograms\end{aligned}[/tex]

Using the momentum conservation equation, to find out final velocity of the system(bullet and block combined)

[tex]m_1v_1+m_2v_2= MV\\[/tex]

[tex]0.0162\times 850+40\times 0 = 40.0162\times V\\V= 0.3441 meter/sec[/tex]

Now using the Conservation of Energy (Kinetic energy of the system will be equal to potential energy in the spring), to find out the displacement of the spring [tex](x)[/tex]

[tex]\frac{1}{2}kx^2 = \frac{1}{2}MV^2\\\\\frac{1}{2}\times 1000\times x^2= \frac{1}{2} \times40.0162\times0.3441^2\\\\x^2= 0.004738\\\\x= 0.06883\ meters[/tex]

Hence, the maximum compression in the spring is 0.06883 meters.

To know more visit:

https://brainly.com/question/2001019

what is the reason that causes viewing obstacle and less in sloar radiation?​

Answers

Answer:

In addition to the sun's angle, atmospheric conditions can affect radiation levels. Cloud cover, air pollution and the hole in the ozone layer all alter the amount of solar radiation that can reach the surface. These factors all cause typical radiation levels to differ.

hope it helps

To solve this, we must be knowing each and every concept behind solar radiation. Therefore, cloud cover, air pollution, and the ozone hole all reduce the quantity of solar energy that reaches the earth's surface.

What is solar radiation?

The energy generated by the sun as just a consequence of vast internal processes is known as solar radiation. In a word, the sun's capacity to generate intense nuclear fusion within and around the core enables it to radiate such vast amounts of energy inside the form of both heat and light. The entire process begins at the core of the sun.

Aside from the sun's angle, meteorological variables can influence radiation levels. Cloud cover, air pollution, and the ozone hole all reduce the quantity of solar energy that reaches the earth's surface. All of these variables contribute to variations in normal radiation levels.

Therefore, cloud cover, air pollution, and the ozone hole all reduce the quantity of solar energy that reaches the earth's surface.

To know more about  solar radiation, here:

https://brainly.com/question/23338147

#SPJ2

what types of cuts do jig saw sanders make?​

Answers

The jigsaw can be used to make both straight and curved cuts in a wide variety of materials, including wood, particleboard, plywood, plastic, metal, even ceramic tile. There is also way more than those, but those are just the basics or common things. Hope this helps!

what type of signal is utilized by the GP's satellite ?

Answers

Answer:

Hi how are you doing today Jasmine

Answer:

The answer is B

Explanation:

I did the USA test prep

help ASAP 100 POINTS

Question 1 (1 point)
According to theory, which term best describes the universe before the big bang?

Question 1 options:

a star


a cloud of gas and dust


a small densely packed ball of matter


a planet

Question 2 (1 point)
Which example is used as evidence that the universe began with the big bang?

Question 2 options:

leftover energy in the form of background radiation in the universe from the event


the force of gravity


craters on the moon


the existence of atoms

Question 3 (1 point)
How do scientists use the Doppler effect to understand the universe?

Question 3 options:

to determine motion of objects


to determine light brightness


to determine planet compositition


to determine the ages of planets

Question 4 (1 point)
The Doppler effect indicates that the universe is expanding because_________.

Which phrase best completes the sentence.

Question 4 options:

light from other galaxies is the same color


light from other galaxies is the different color


light from other galaxies is blue shifted


light from other galaxies is red shifted

Question 5 (1 point)
What does a blue shift in light from stars indicate?

Question 5 options:

The stars are moving randomly.


The stars are moving closer.


The stars are moving farther away.


The stars are stationary.

Answers

Answer:

Explanation:

Question 1 (1 point)

According to theory, which term best describes the universe before the big bang?

a small densely packed ball of matter

Question 2 (1 point)

Which example is used as evidence that the universe began with the big bang?

Question 2 options:

leftover energy in the form of background radiation in the universe from the event

Question 3 (1 point)

How do scientists use the Doppler effect to understand the universe?

to determine motion of objects

 

Question 4 (1 point)

The Doppler effect indicates that the universe is expanding because_________.

Which phrase best completes the sentence.

light from other galaxies is red shifted

Question 5 (1 point)

What does a blue shift in light from stars indicate?

The stars are moving closer.

Calculate the electric field intensity
at a Point 15cm from a charge of 10 uc​

Answers

Answer:

it's very easy and simple answer u can't do it

The electric field intensity at a point of 15cm from a charge of 10 μc will be 3.9 ×10⁶ N/C.

What is the intensity of the electric field?

The electric field is defined as the area over an electric charge where its impact may be felt. The force experienced by a unit positive charge deposited at a given position is known as the electric field intensity.

The formula for the electric field intensity is given as;

[tex]\rm E= \frac{q}{4 \pi \epsilon d^2 } \\\\ \rm E= \frac{10 \times 10^{-6}}{4 \times 3.14 \times 8.85 \times 10^{-12}(15 \times 10^{-2}^2 } \\\\ E=3.9 \times 10^6 \ NC^{-1}[/tex]

Hence the electric field intensity at a point of 15cm from a charge of 10 μc will be 3.9 ×10⁶ N/C.

To learn more about the intensity of the electric field refer to the link;

https://brainly.com/question/26446532

Please please help me please please help please please help me please

Answers

Answer:

I think its D, Does the wave travel In a Vaccum?

Answer:

It's C. Does the wave transfer energy?

map.
Which best describes the motion of the object
between 1 and 4 seconds?
کے م
The object has decreasing acceleration and
increasing velocity.
The object has positive acceleration and eventually
stops.
The object has decreasing acceleration and
decreasing velocity.
The object has negative acceleration and eventually
stops.

Answers

Answer:

The object has decreasing acceleration and decreasing velocity.

A charged rod is brought near one end of a long, uncharged metal block. Students want to experimentally measure the resulting charge distribution along the entire length of the block. They have a small, positively charged sphere on a string that can be used as a test charge with negligible effect on the other charges. They will observe whether the sphere is attracted or repelled when held near the rod. Which of the following describes and justifies a procedure that will provide data to determine the entire charge distribution?

a. Hold the sphere near the end of the block closest to the rod, because that will give experimental data about both ends of the block.
b. Hold the sphere near each end of the block, because that will give experimental data about both ends of the block.
с. Hold the sphere near each end of the block and near the block's middle, because that will give experimental data about the area along the length of the block.
d. Hold the sphere near each end of the block and at a number of points along the length of the block, because that will give experimental data for the whole block.

Answers

Answer:

d

Explanation:

The sphere is positively charged so that when it comes in contact with the rod, its positive charges will repel to the other end. Hence, Hold the sphere near each end of the block, because that will give experimental data about both ends of the block.

What is polarization?

Polarization is the separation of charges into two poles due electrostatic repulsion. Two similar charges will repel and opposite charges attracts each other.

When a charged or polar substance get in contact with a non-polar substance, the nonpolar one will deform in such a way that the electrons from the polar one will repel the electrons of nonpolar and there occurs a temporary charge separation in non polar substance creating an induced polarity.

Here, when the positive sphere comes in contact with the charged rod, the positive charges will align to the opposite pole of the rod away from the sphere and the negative charges will align near the sphere.

Thus there occurs an attractive force at one end and repulsion at the other end. Thus, holding the sphere at each end will data about charge distribution.

To find more on polarization, refer here:

https://brainly.com/question/29217577

#SPJ5

Consider a composite cube made of epoxy with fibers aligned along one axis of the cube (the fibers are parallel to four of the twelve cube edges). If the cube can only be loaded in axial tension such that the force is uniformly applied over - and is normal to - a cube face, what is the lowest possible positive length change the cube can experience under this tension

Answers

The question is incomplete. The complete question is :

Consider a composite cube made of epoxy with fibers aligned along one axis of the cube (the fibers are parallel to four of the twelve cube edges). If the cube can only be loaded in axial tension such that the force is uniformly applied over - and is normal to - a cube face, what is the lowest possible positive length change the cube can experience under this tension? The applied tensile force is 102 KN. The unloaded cube edge length is 56 mm. The glass fibers have an elastic modulus of 200 GPa. The epoxy has an elastic modulus of 38 GPa. The cube is comprised of 18 vol% epoxy (the balancing vol % is glass fiber). Hint: The loading axis is intentionally unspecified. Answer Format: Lowest possible length increase (change of length) under tension.

Solution :

Given :

[tex]$E_{glass fibre}$[/tex] = 200 GPa

[tex]$V_{glass fibre} = 82\%$[/tex]

[tex]$E_{epoxy}$[/tex] = 38 GPa

[tex]$V_{epoxy} = 82\%$[/tex]

Edge length = 56 mm

Cube is loaded in axial tension such that the force is uniformly applied over a cube face.

[tex]$E_{\text{composite}}=\frac{E_{glass fibre} \times E_{epoxy}}{(E_{glass fibre .E_{epoxy}})+(E_{fibre}.V_{glass fibre})}$[/tex]

[tex]$E_{composite} = \frac{200 \times 38}{(200 \times 0.18)+(38\times 0.82)}$[/tex]

               [tex]$=113.16 $[/tex]  GPa

Applied stress [tex]$=\frac{\text{applied load}}{\text{area}}$[/tex]

                    [tex]$\sigma=\frac{102 \times 10^3 \ N}{56 \times 56 \times 10^{-6} \ m^2}$[/tex]

                       = 32.5 MPa

By Hooke's law

[tex]$\sigma = E . \epsilon$[/tex]

[tex]$\sigma = E. \frac{\Delta l}{l}$[/tex]

[tex]$\Delta l = \frac{\sigma}{E}\times l$[/tex]

Length change, [tex]$\Delta l =\frac{32.5 \times 10^6 \ Pa}{113.16 \times 10^9 \ Pa}\times 56 \times 10^{-2} \ m$[/tex]

[tex]$\Delta l = \frac{32.5 \times 56}{113.16} \times 10^{-3} \ mm$[/tex]

   = 0.016 mm

What is the centripetal force for a roller coaster if the mass is 10 kg and the normal force is 25 N?

Answers

Answer:

Fc = 123 Newton

Explanation:

Net force can be defined as the vector sum of all the forces acting on a body or an object i.e the sum of all forces acting simultaneously on a body or an object.

Mathematically, net force is given by the formula;

[tex] Fnet = Fapp + Fg[/tex]

Where;

Fnet is the net force.

Fapp is the applied force.

Fg is the force due to gravitation.

Given the following data;

Normal force = 25N

Mass = 10kg

To find the centripetal force;

From the net force, we have the following formula;

Fc = N + mg

Where;

Fc is the centripetal force.

N is the normal force.

mg is the the weight of the object.

Substituting into the formula, we have;

Fc = 25 + 10(9.8)

Fc = 25 + 98

Fc = 123 Newton

why do trucks need a runaway ramp

Answers

Answer:

in case they lose control going downhill.

Explanation:

which is why they usually have a steep incline and are quite long. You see them used typically when the trucks brakes fail.

A grindstone in the shape of a solid disk has a shaft attached to allow a force to be exerted on. The grindstone has a diameter of 0.650m and a mass of 55.0 kg. The shaft is 0.300 m from the center of the stone and has a mass of 4.00 kg. The grindstone has a motor attached and it is rotating at 450rev/min at a run when the motor is shut off. The grindstone comes to rest in 9.50 s.
a. What is the moment of inertia of the grindstone including the shaft?
b. What is the angular acceleration of the grindstone?
c. What average torque is done by friction to bring the grindstone to rest?
d. How many revolutions has it taken the grindstone to come to rest?
e. What is the linear acceleration of the shaft in this process?
f. What is the linear distance that the shaft traveled?

Answers

Answer:

a)  3.265 kg-m^2

b)  - 4.96  rad/s^2

c) 16.1944 N-m

d) 35.625

e)  - 1.488 m/s^2

f)  67.1175 m.

Explanation:

Given data:

Diameter of grindstone ( D ) = 0.650 m ,  Radius ( R ) = 0.325 m

mass of grindstone ( M ) = 55 kg

Radius of shaft ( r ) = 0.300 m

mass of shaft ( m ) = 4 kg

Initial Angular velocity = 450 rev/min = f = 7.5 rev/s = w  =15π rad/s

time ( t ) = 9.50 secs

a) Determine the moment of inertia of the grindstone including the shaft

moment of inertia of grindstone = MR^2 / 2 = 55* (0.325)^2 / 2 = 2.905

moment of inertia of shaft = mr^2 = 4 *0.3^2 = 0.36

∴ moment of inertia including shaft = 2.905 + 0.36 = 3.265 kg-m^2

b) Determine the angular acceleration of the grindstone

∝ = - 15π / 9.5 ( i.e.  angular velocity / time )

   = - 4.96  rad/s^2 ( deceleration value )

c) Determine average torque done by friction to bring the grindstone to rest

Torque ( I * ∝ )  = 3.265 x 4.96 = 16.1944 N-m (magnitude)

d) Determine the number of revolutions before grindstone comes to rest

Total revolutions N before grindstone comes to rest

= ( f1 + f2)* t /2 = 7.5 * 9.5 / 2 = 35.625

Note : f2 = 0 as it comes to rest

          f1 = 7.5 rev/s

e) Determine the Linear acceleration of the shaft in this process

This can be calculated using this relation

r * ∝ = 0.3 x (- 4.96 ) = - 1.488 m/s^2

f) Determine the linear distance travelled by the shaft

This can be calculated with the relation below

r * 2 * π * N = 0.3 * 2π * 35.625 = 67.1175 m.


Which of the following is most consistent with the modern theory of evolution?
O Parents pass their physical traits to their offspring; those offspring with traits that help the
O Parents change their physical traits in order to survive in the environment, then those pa
O Life on this planet came from another planet far out in space.
O Living organisms have not changed for hundreds of millions of years.

Answers

Answer:

The theory of evolution by natural selection, first formulated in Darwin's book "On the Origin of Species" in 1859, is the process by which organisms change over time as a result of changes in heritable physical or behavioral traits

[tex] \sf{ What \: is \: a \: parallel \: circuit? }[/tex]
[tex] \\ \\ \\ \\ \\ [/tex]

Answers

Answer:

parallel circuit is a kind of circuits in which all components are connected between the same two sets of electrically common points, creating multiple paths for the current to flow from one end of the battery to the other:

Answer:

Gadhe hote hai log and usme sabse pehele aati hai Jonain jaise log waah waah xD

Brainliest krdena warna chappal padenge -,-

A column of argon is open at one end and closed at the other. The shortest length of such a column that will resonate with a 200 Hz tuning fork is 42.5 cm. The speed of sound in argon must be: Group of answer choices

Answers

Answer:

The speed of sound in the argon is 340 m/s.

Explanation:

Given;

fundamental frequency, f₀ = 200 Hz

length of the pipe, L = 42.5 cm = 0.425 m

A pipe that is open at one end and closed at another end is known as a closed pipe.

The wavelength for the first harmonic is calculated as;

L = Node -------> Antinode

L = λ/4

λ = 4L

The speed of the sound is calculated as;

v = fλ

where;

v is the speed of the sound

v = f x 4L

v = 200 x (4 x 0.425)

v = 340 m/s

Therefore, the speed of sound in the argon is 340 m/s.

When you blow across the top of a soda bottle, it acts like a closed pipe. If the inside of the bottle is 0.150 long, what is the fifth harmonic frequency

Answers

Answer:

The fifth harmonic frequency is 2.9 KHz.

Explanation:

For a closed tube, the fifth harmonic frequency is also the second overtone. So that;

fifth harmonic frequency = [tex]\frac{5V}{4L}[/tex]

where V is the velocity of the sound in air, and L is the length of the tube.

But L = 0.15 m and V = 343 m/s, then:

fifth harmonic frequency = [tex]\frac{5*343}{4*0.15}[/tex]

                                     = [tex]\frac{1715}{0.6}[/tex]

                                     = 2858.33 Hertz

fifth harmonic frequency = 2.9 KHz

The fifth harmonic frequency of the soda bottle is approximately 2.9 KHz.

Answer:

2828.33

Explanation:

answer for acellus


1. What exactly is science?
Write the definition of
science in your own words.

Answers

the intellectual and practical activity encompassing the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.

Answer:

A practical activity about the study of the structure of the natural and physical world that can be shown thorough experiments and study's.

Explanation:

the path of the earth around the sun is called​

Answers

Answer:

Orbit.

Explanation:

An orbit is a regular, repeating path that one object in space takes around another one, it's an imaginary path of the Earth around the Sun.

What happened to the combined energy of the two sleds when they collided?

Answers

Hi!
Here’s your answer:

What happened to the combined energy of the two sleds when they collided? It changed forms into another energy C. Because energy is conserved, the “lost” energy has actually been changed into other forms.

Hope this helps have a good day!!<3

Combined energy of the two sleds will be conserved when they collides.

What is Energy ?

Energy is nothing but the ability to do work. there are different energies in different form which are thermal energy, mechanical energy, electric energy and sound energy etc.

According to first law of thermodynamic, Energy neither be created nor be destroyed. it can only be transferred from one form into another form. Energy is expressed in joule (J). its dimensions are [M¹ L² T⁻²].

Energy is conserved throughout the motion,

according to conservation law of energy, initial energy is equal to final energy.

When two sleds coming in opposite direction, it is having mass as well as velocity. hence it has kinetic energy, when they get collide with each other some of total energy gets converted into sound energy as collision cause sound(boom). some of the energy will use to break the material which made the sled and remaining energy will convert in kinetic energy of broken sleds it can be moved in opposite direction or in same direction depending initial energies.

in this collision combined kinetic energy can be converted into sound energy, mechanical energy and again kinetic energy but totally energy is conserved.

Hence combined energy will be conserved.

To know more about energy :

https://brainly.com/question/1932868

#SPJ3.

What’s the answer to 19 please please help me

Answers

Answer:

A.

Explanation:

A po sa tingin ko

sana po makatulong

Answer A it transmits red and absorbs all the other colors

Which of the following creates the night-and-day cycle experienced on Earth?
A) Orbit of Earth around the Sun
B) Rotation of the Sun
C) Rotation of the Earth
D) Tilt of the axis of Earth

Answers

the answer should be C

The Chernobyl reactor accident in what is now Ukraine was the worst nuclear disaster of all time. Fission products from the reactor core spread over a wide area. The primary radiation exposure to people in western Europe was due to the short-lived (half-life 8.0 days) isotope 131I
131 I, which fell across the landscape and was ingested by grazing cows that concentrated the isotope in their milk. Farmers couldn't sell the contaminated milk, so many opted to use the milk to make cheese, aging it until the radiactivity decayed to acceptable levels. How much time must elapse for the activity of a block of cheese containing 131I 131 I to drop to 1.0% of its initial value?

Answers

Answer:

The correct answer is "53.15 days".

Explanation:

Given that:

Half life of [tex]131_{I}[/tex],

[tex]T_{\frac{1}{2} }= 8 \ days[/tex]

Let the initial activity be "[tex]R_o[/tex]".and, activity to time t be "R".

To find t when R will be "1%" of [tex]R_o[/tex], then

⇒ [tex]R=\frac{1}{100}R_o[/tex]

As we know,

⇒ [tex]R=R_o e^{-\lambda t}[/tex]

or,

∴ [tex]e^{\lambda t}=\frac{R_o}{R}[/tex]

By putting the values, we get

        [tex]=\frac{R_o}{\frac{R}{100} }[/tex]

        [tex]=100[/tex]

We know that,

Decay constant, [tex]\lambda = \frac{ln2}{T_{\frac{1}{2} }}[/tex]

hence,

⇒ [tex]\lambda t=ln100[/tex]

     [tex]t=\frac{ln100}{\lambda}[/tex]

        [tex]=\frac{ln100}{\frac{ln2}{8} }[/tex]

        [tex]=53.15 \ days[/tex]  

Please help me ASAP!!

Answers

Answer:

the ball lose kentic energy and gains potential energy rolling upward

Answer:

c

Explanation:

when a ball is rolling down it loses potential and gains kinetic, but in this case since the ball is going upwards it is losing kinetic energy and gaining potentail like a roller coaser

A ladder 25 feet long is leaning against the wall of a house. The base of the ladder is pulled away from the wall at a rate of 2 feet per second. (a) What is the velocity of the top of the ladder when the base is given below

Answers

This question is incomplete, the complete question is;

A ladder 25 feet long is leaning against the wall of a house. The base of the ladder is pulled away from the wall at a rate of 2 feet per second. (a) What is the velocity of the top of the ladder when the base is given below

7 feet away from the wall

15 feet away from the wall

20 feet away from the wall

Answer:

- When x is 7 feet away from the wall, [tex]\frac{dr}{dt}[/tex] = -7/12 ft/s

- When x is 15 feet away from the wall, [tex]\frac{dr}{dt}[/tex] = -3/2 ft/s

- When x is 20 feet away from the wall, [tex]\frac{dr}{dt}[/tex] = -8/3 ft/s

Explanation:

Given the data in the question;

Let [tex]r[/tex]ft and [tex]x[/tex]ft represent the distance of the top of ladder from the ground and the distance of the bottom of ladder from the wall respectively.

Now using the Pythagoras Theorem ( right angled triangle ).

(hypotenuse)² = ( adjacent )² + ( opposite )²

so

r² = ( 25 )² - x²

r² = 625 - x² ------- let this be equation 1

now, we differentiate with respect to t

2r [tex]\frac{dr}{dt}[/tex] = 0 - 2x [tex]\frac{dx}{dt}[/tex]

r [tex]\frac{dr}{dt}[/tex] = -x [tex]\frac{dx}{dt}[/tex]

[tex]\frac{dr}{dt}[/tex] = -x [tex]\frac{dx}{dt}[/tex] × 1/r

[tex]\frac{dr}{dt}[/tex] = -x/r [tex]\frac{dx}{dt}[/tex]

Now, from equation, r² = 625 - x²

r = √( 625 - x² )

Then

[tex]\frac{dr}{dt}[/tex] = -x / √( 625 - x² ) [tex]\frac{dx}{dt}[/tex]

given that, The base of the ladder is pulled away from the wall at a rate of 2 feet per second i.e [tex]\frac{dx}{dt}[/tex] = 2 ft/s

so;

[tex]\frac{dr}{dt}[/tex] = ( -x / √( 625 - x² ) ) × 2

[tex]\frac{dr}{dt}[/tex] = -2x / √( 625 - x² )

When x is 7 feet away from the wall;

[tex]\frac{dr}{dt}[/tex] = -2(7) / √( 625 - (7)² )

[tex]\frac{dr}{dt}[/tex] = -14 / √( 625 - 49 )

[tex]\frac{dr}{dt}[/tex] = -14 / √576

[tex]\frac{dr}{dt}[/tex] = -14 / 24

we simplify

[tex]\frac{dr}{dt}[/tex] = -7/12 ft/s

Therefore, When x is 7 feet away from the wall, [tex]\frac{dr}{dt}[/tex] = -7/12 ft/s

When x is 15 feet away from the wall

[tex]\frac{dr}{dt}[/tex] = -2(15) / √( 625 - (15)² )

[tex]\frac{dr}{dt}[/tex] = -30 / √( 625 - 225 )

[tex]\frac{dr}{dt}[/tex] = -30 / √400

[tex]\frac{dr}{dt}[/tex] = -30 / 20

we simplify

[tex]\frac{dr}{dt}[/tex] = -3/2 ft/s

Therefore, When x is 15 feet away from the wall, [tex]\frac{dr}{dt}[/tex] = -3/2 ft/s

When x is 20 feet away from the wall

[tex]\frac{dr}{dt}[/tex] = -2(20) / √( 625 - (20)² )

[tex]\frac{dr}{dt}[/tex] = -40 / √( 625 - 400 )

[tex]\frac{dr}{dt}[/tex] = -40 / √225

[tex]\frac{dr}{dt}[/tex] = -40 / 15

we simplify

[tex]\frac{dr}{dt}[/tex] = -8/3 ft/s

Therefore, When x is 20 feet away from the wall, [tex]\frac{dr}{dt}[/tex] = -8/3 ft/s

Which of the following best explains the greater difficulty in stopping a 1000-kg car
moving at 174 km/h compared to an identical 1000-kg car moving at 100 km/h?

Answers

Stopping a 1000 kg car moving at a speed of 174 km/h will be more difficult than stopping an identical car moving at 100 km/h.

This can be explained by using Newton's second law of motion which says that the rate of change of momentum of a body is equal to the force applied.

We know that momentum of a body is the product of its mass and velocity.The momentum of the car moving at 174 km/h = [tex]1000\, kg \times 174\, km/h = 174000 \, kg.km/h[/tex].The momentum of the car moving at 100 km/h = [tex]1000\, kg \times 100\, km/h=100000 kg.km/h[/tex].

Therefore, the car moving at 174 km/h has higher momentum and from Newton's second law of motion, a higher force would be required to stop this car.

Learn more about Newton's second law of motion here:

https://brainly.com/question/13447525?referrer=searchResults

What was the name of the voyages taken by Zheng he during the Ming dynasty on behalf of China

Answers

Answer:

Ming treasure voyages

Explanation:

NO LINKS: Which of the following best demonstrates Newton's Third Law?

Gravity is a force pulling down on you.

The ahrder you hit a volleyball the faster it will get over the net

Air resistance slows down a parachutist

Your foot pushing on the floor and the floor pushing back

Answers

The best demonstration that applies to Newton's Third Law of motion would be D) When you walk your foot pushes down on the ground while the ground pushes back on your foot.

------------------

Newton's Third Law states that for every action, there is an equal and opposite reaction. This is actually explains that forces come in pairs and forces are an interaction between two objects. As per the correct option given in the question explains Newton’s Third Law.  

------------------

When you walk your foot (say object A) pushes down on the ground while the ground (say object Q) pushes back on your foot with the same force but in the opposite direction.

a girl stands on a boat and feels the boat rise and fall 7 times In 1 minute. what is the period of the water wave? give your answer to 3 significant figures​

Answers

Explanation:

hope it's helpful

have a nice day!!!! ;)

Other Questions
Write a critique of a comedy or comedic essay. PLZ HELP!!! WILL GIVE BRAINLIST!!!It says WRITE A boat can travel 395 miles on 79gallons of gasoline. How far can it travelon 21 gallons? Which of the following is an example of a molecular element?a.NaCl b. CO2 c. Na d. O2 2. A six sided cube was rolled. What is the probability of showing an odd number?"2 points10%30%50 %1% Hot water is poured into four cups made of different materials (foam, glass, metal, plastic).After one minute, which will feel the warmest when you touch the OUTSIDE of the cup? what is this equation ?4008 - 1759 BACK provides guidelines for safe lifting.O True0 False 6. Fill in the blank in the following sentence with the appropriate form of quel. _____________ ligne de mtro va la bibliothque nationale?15. Fill in the blank in the following sentence with the appropriate container.Il y a une ________ de vin blanc dans le frigo.26. Unscramble the following words to compose a complete sentence. Remember to conjugate the verb.ne / vous / boire / pouvoir / vin / de /pas31. Unscramble the following words to compose a complete sentence. Remember to conjugate the verb.lire / le / tous / journal/ nous / jours / les HELP PLZ!! Pick the word that best completes the following sentence.In Mexiko spricht man ______.SpanischDeutschLandkarteLicht The graph of f(x) and g(x)=f(x) + k is shown on the coordinate plane.k = _ ? 1)Escribe oraciones coherentes que incluyan los siguientes trminos con los conceptos correspondientes:CARBN-PETRLEO-GAS NATURAL-RECURSO NO RENOVABLE-COMBUSTIBLES FSILES-HIDROCARBUROS-RESERVAS-CONTAMINACIN-MAREAS NEGRAS What two types of people were used to grow crops after the civil war? Difference between training and exercise EnglishNo links! I will report themSchool of Hard Knotsby Alex Hanson Options:1)It is no wonder, then, that as a generation of Japanese boatwrights has retired, their knowledge has retired with them.2) through his talk, Brooks has stimulated A debate how traditional crafts are headed down. His American audience expect collegiality Oh and dialogue between student and teacher and are often shocked to hear about the Japanese method.3) unless an apprentice was the master son, he could expect to have a steel essential piece of knowledge from the master, either by sneaking into the shop to take measurements or buy other subterfuge.4) they would talk about their craft with a commitment and a sense of idea that you never hear in the west he says. a math class surveyed the musical prefences of 42 students. use their data file to write a ratio for each comparison the three different ways for a,b and c Balloon has a volume of 600-ml at temperature of 360 K. If the temperature ofthe balloon drops to 250 K, find the volume Give examples of how land resources are used in a city setting 3. Which choice below is an approximate volume of oil that the tankbelow can hold?78 ft. **25 ft.OIL TANK*WHAT IS THE ANSWER* please help me i love u Find the value of x.