Please help me

Think about a time when you walked down an empty hallway
and heard the echo of your footsteps. Write what you think
caused the echo.

Answers

Answer 1

Answer:

Explanation:

There are a few conditions as mentioned:  "you walked down an empty hallway and heard the echo of your footsteps." So first thing is as you walk, your shoes touch the floor and make noises.  Those are sounds of your footsteps.  You are in a hallway so the sounds are trapped within the hallway.  It is empty so there is nothing like people who would block and absorb the sounds. With sounds bouncing around walls and floor of the hallway, they bounce back to the source: you. That is when you hear the echo of your footsteps.


Related Questions

A 80kg astronaut is training in human centrifuge to prepare for a launch. The astronaut uses the centrifuge to practice having a 3.16g force (3.16 times his own weight) on his back. The radius is 12m.
Attached is a picture of the question.

Answers

The answers on the model of the human centrifuge ready for the launch to each question of the statement are listed below:

a) A force of 2479.210 newtons is acting on the astronaut's back.

b) A net centripetal force of 2479.210 newtons is acting on the astronaut.

c) The centripetal acceleration of the astronaut is 30.990 meters per square second.

d) The astronaut has a linear speed of approximately 19.284 meters per second.

e) The angular speed of the astronaut is 1.607 radians per second (15.346 revolutions per minute).

How to apply Newton's laws to analyze a process in a human centrifuge training

The human centrifuge experiments a centripetal acceleration when it reaches a peak angular speed. In this question we must apply Newton's laws of motion and concepts of centripete and centrifugal forces to answer the questions. Now we proceed to answer the questions:

How much force is acting on the astronaut's back?

By the third Newton's law the astronaut experiments a rection force (F), in newtons, which has the same magnitude to centrifugal force but opposed to that force. The magnitude of the force acting on the back of the astronaut is equal to:

[tex]F = 3.16\cdot (80\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)[/tex]

[tex]F = 2479.210\,N[/tex]

A force of 2479.210 newtons is acting on the astronaut's back. [tex]\blacksquare[/tex]

What is the net centripetal force on the astronaut?

By the second and third Newton's laws we know that the net centripetal force on the astronaut is equal to the magnitude of the force found in the previous question. Thus, a net centripetal force of 2479.210 newtons is acting on the astronaut. [tex]\blacksquare[/tex]

What is the astronaut's centripetal acceleration?

The centripetal acceleration of the astronaut (a), in meters per square second, is found by dividing the result of the previous question by the mass of the astronaut (m), in kilograms:

[tex]a = \frac{F}{m}[/tex]   (1)

If we know that F = 2479.210 newtons and m = 80 kilograms, then the centripetal acceleration of the astronaut is:

[tex]a = \frac{2479.210\,N}{80\,kg}[/tex]

[tex]a = 30.990\,\frac{m}{s^{2}}[/tex]

The centripetal acceleration of the astronaut is 30.990 meters per square second. [tex]\blacksquare[/tex]

What is the astronaut's linear speed?

By definition of uniform circular motion, we have the following formula for the linear velocity of the astronaut (v):

[tex]v = \sqrt{a\cdot r}[/tex]   (1)

Where r is the radius of the human centrifuge, in meters.

If we know that [tex]a = 30.990\,\frac{m}{s^{2}}[/tex] and [tex]r = 12\,m[/tex], then linear velocity of the astronaut is:

[tex]v = \sqrt{\left(30.990\,\frac{m}{s^{2}} \right)\cdot (12\,m)}[/tex]

v ≈ 19.284 m/s

The astronaut has a linear speed of approximately 19.284 meters per second. [tex]\blacksquare[/tex]

What is the astronaut's angular speed?

The angular speed of the astronaut (ω), in radians per second, is found by the following kinematic relationship:

[tex]\omega = \frac{v}{R}[/tex]   (1)

If we know that v ≈ 19.284 m/s and R = 12 m, then the angular speed is:

[tex]\omega = \frac{19.284\,\frac{m}{s} }{12\,m}[/tex]

ω = 1.607 rad/s (15.346 rev/m)

The angular speed of the astronaut is 1.607 radians per second (15.346 revolutions per minute). [tex]\blacksquare[/tex]

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What is the 3rd largest planet in the solar system?

Answers

Answer:

Uranus

Explanation:

Your welcome

A planet is a celestial body. The third-largest planet in the solar system is Uranus.

What is a planet?

A celestial body is differentiated from the fixed stars by its apparent mobility (including the moon and sun), especially in relation to its claimed impact on people and events.

A planet is a celestial body. The third-largest planet in the solar system is Uranus.

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Please help asap its for anatomy

explain the basic mechanical process through which micturition occurs, including an explanation of why someone might not be able to "hold it in" any longer if they wait too long to urinate and why it might be harder for older people to hold their urine for a long time

Answers

The smooth muscle in the wall of the bladder when stretched triggers the micturition reflex (urination).

What is a Bladder?

This is defined as a lined layers of muscle tissue that stretch to hold urine in organisms.

In older people the elasticity of the bladder is reduced which is why it makes it harder for them to hold urine for a long time.

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Use F = 1/T as your basis:
7. What is the period of 60.0Hz electrical power?

The answer is 16.7 ms but please show your work.

Answers

Frequency=60Hz

[tex]\\ \rm\rightarrowtail \nu=\dfrac{1}{T}[/tex]

[tex]\\ \rm\rightarrowtail T=\dfrac{1}{\nu}[/tex]

[tex]\\ \rm\rightarrowtail T=\dfrac{1}{60}[/tex]

[tex]\\ \rm\rightarrowtail T=1.67\times 10^{-4}s[/tex]

[tex]\\ \rm\rightarrowtail T=16.7\times 10^{-3}s[/tex]

[tex]\\ \rm\rightarrowtail T=16.7ms[/tex]

How does a white dwarf compare to our sun as it exists now?.

Answers

Answer:

answer down below

Explanation:

it has similar mass but the white dwarf is much denser

What do tripped circuit breakers and blown fuses indicate.

Answers

Answer:

When a circuit breaker regularly trips or a fuse repeatedly blows, it is a sign that you are making excessive demands on the circuit and need to move some appliances and devices to other circuits. Or, it may indicate that your house has too few circuits and is in need of a service upgrade.

The term group polarization refers to the tendency for.

Answers

Polarization refers to the tendency for acquiring specific orientation by the oscillation.

What is polarization?

Polarization is a property that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular as compared to other that have parallel.

So we can conclude that Polarization refers to the tendency for acquiring specific orientation by the oscillation.

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Which of the following was correctly predicted by Einstein's theory of gravity?
(A) the origin of mass
(B) law of refraction
(C) the measure of G
(D) light deflected around large objects because of their gravity

Answers

Answer:

(D) light deflected around large objects because of their gravity

I hope this helps you

:)

16. By how much leeway (both percentage and mass) would you have in the selection of the mass of the object in the previous problem if you did not wish the new period to be greater than 2.01 s or less than 1.99 s?

Please show all of your work.

Answers

Here is the solution for previous question

[tex]\\ \rm\rightarrowtail T=2\pi\sqrt{\dfrac{m}{k}}[/tex]

[tex]\\ \rm\rightarrowtail T\propto \sqrt{m}[/tex]

Hence

[tex]\\ \rm\rightarrowtail \dfrac{T_1}{T_2}=\sqrt{\dfrac{m1}{m2}}[/tex]

[tex]\\ \rm\rightarrowtail \dfrac{1.5}{2}=\sqrt{\dfrac{0.5}{m2}}[/tex]

[tex]\\ \rm\rightarrowtail 0.75^2=\dfrac{0.5}{m2}[/tex]

[tex]\\ \rm\rightarrowtail m_2=\dfrac{0.5}{0.75^2}[/tex]

[tex]\\ \rm\rightarrowtail m_2=0.888888888\dots[/tex]

So

from this

So it's infinite in terms of 8 so must be greter than one 8

We rounded it up for 3 decimals

0.889kg

So

Error range=[1.99,2.01]

∆Error=2.01-1.99=0.02

Very mere one

Now find percentage

[tex]\\ \rm\rightarrowtail \dfrac{0.02}{2}(100)=0.01(100)=1\%[/tex]

Mass should be lied in

0.01(0.889)=0.00889 kg

But for increase mass

it would be

0.00889-0.00500=0.00389kg

A round tube weighs 30 lbs. If the tube is stood on end it pushes down on the floor with a pressure of
2 lbs/in?. How many square inches is the end of the tube?

Answers

Answer:

15in2

Explanation:

The diagram shows part of a radio antenna.The plastic tube protects the radio antenna from bad weather.Dust particles carried by the wind rub against the plastic tube.After some time, the dust particles cause the tube to become positively charged.State the property of plastic that allows it to become electrostatically charged.

Have a good day!! :>

easy one here pls help thanks so much

Answers

The answer is B. Nutrients.
the answer is B. Nutrients

how can you say metre cube is a derived unit​

Answers

Answer:

The newton (lowercase n!) is a derived unit because its definition consists of multiplication of three defined base units and nothing else. Its meaning is thus derived, not independently defined.

(please answer) It is better to jump on a smooth, flat surface than on thick carpeting.

Question 5 options:
True
False

Answers

I believe the answer to your question would be True

I think it would have to be true.

What is current of 12 ohm? help me pleasee​

Answers

Answer:

2.5A

Explanation:

We know the relation :

V = IR

V = voltage (potential difference)I = currentR = resistance

By using the formula,

I = V/RI = 30/12I = 10/4I = 2.5A

Answer :-

Current of Device = 2.5 Ampere .

Explanation :-

As per the provided information in the given question, we have been given that the Potential Difference is 30 Volt . The Resistance is given as 12 Ohm . And, we have been asked to calculate the Current of the Device.

For calculating the Current , we will use the Formula :-

[tex] \bigstar \: \: \: \boxed { \sf{ \: Current \: = \: \dfrac{Potential \: Difference}{Resistance} \: }} [/tex]

Therefore , by Substituting the given values in the above Formula :-

[tex] \dag \: \: \: \sf { Current \: = \: \dfrac{Potential \: Difference}{Resistance} } [/tex]

[tex] \longmapsto \: \: \: \sf { Current \: = \: \dfrac{30}{12} } [/tex]

[tex] \longmapsto \: \: \: \textbf {\textsf {Current \: = \: 2.5 }} [/tex]

Hence :-

Current = 2.5 Ampere .

[tex]\underline {\rule {180pt} {4pt}} [/tex]

What does the text mean when it says “naming an elements is like creating history

Answers

Answer: When you name an element, it's usually because the element is newly discovered. So by naming an element you are creating something that will last throughout history.

Explanation:

When using a different calorimeter, and mixing 50 ml of hot water at 65 degrees c with 60 ml of water in the calorimete

Answers

The specific heat capacity of the calorimeter used in mixing the water is determined as 21.87 J/g⁰C.

Conseervation of energy

The heat capacity of the calirometer is determined by applying the principle of conservation of energy.

Heat lost by the hot water = Heat gained by the calirometer

[tex]Q _w = Q_c\\\\M_w C_w\Delta \theta _w = M_c C_c\Delta \theta _c[/tex]

where;

M is mass

mass = density x volume = ρV

Density of water = 1 g/ml

Mass of hot water = 1 x (50) = 50 g

Mass of water in calorimeter = 1 x (60) = 60 g

Equilibrium temperature

[tex]\Delta T_c = 5.5\\\\T - 25 = 5.5\\\\T = 30.5 \ ^0C[/tex]

Specific heat capacity of the calirometer

[tex]50 \times 4.184 \times (65 - 30.5) = 60 \times C_c \times (30.5 - 25)\\\\7217.4 = 330C_c\\\\C_c = \frac{7217.4}{330} \\\\C_c = 21.87 \ J/g^0C[/tex]

Thus, the specific heat capacity of the calorimeter used in mixing the water is determined as 21.87 J/g⁰C.

The complete question is below

When using a different calorimeter, and mixing 50 ml of hot water at

65 degrees C with 60 ml of water in the calorimeter at 25 degrees C, the temperature of the calorimeter increased by 5.5 degrees C.

a. Calculate the heat capacity of this calorimeter?

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A man pushes a 8 kg object. A distance of 5. 0 m upward along a frictionless slope that makes an angle of 30° with the horizontal. His force is parallel to the slope. If the speed of the object decreases at a rate of 1. 5 m/s, then the work done by the man is:​

Answers

Answer:

is 200 J

Explanation:

hope this is the right answer

Collette is twisting a screwdriver. The scredriver has a handle with a radius of 18 mm. If she is exerting a force of 14 N, how much torque is she causing? PLEASE HELPPP!!!!

A. 25 Nm
B. 0.25 Nm
C. 1.3 Nm
D 0.75 Nm

Answers

Radius=18mm=1.8cm=0.018mForce=14N

Torque:-

[tex]\\ \rm\Rrightarrow \tau =14(0.018)[/tex]

[tex]\\ \rm\Rrightarrow \tau=0.25Nm[/tex]

option B

Why did astronomers suspect an eighth planet beyond uranus? how did they determine where to look for it? construct the correct explanation.
drag the terms on the left to the appropriate blanks on the right to complete the sentences.

brightness - mass - orbit - position - kepler's third law - value - law of gravity


observation of uranus showed small but significant discrepancy between its predicted ______ and its actual ________ , which could mean that another object perturbed its motion.
in the mid-1800s, astronomers used the ________ to predict where a planet would have to be.

Answers

Astronomers suspected an eighth planet beyond Uranus because of the irregularities in the motion of Uranus suggested that gravity from another planet was affecting it.

Who is an astronaut?

It should be noted that an astronaut simply means an individual who is trained to travel in spacecrafts.

In this case, astronomers suspected an eighth planet beyond Uranus because of the irregularities in the motion of Uranus suggested that gravity from another planet was affecting it.

In mid-1800s, astronomers used the orbits of most asteroids to predict where a planet would have to be.

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Can you hear the vibrations a tuning fork puts off when hit?

Answers

no

Explanation:

no not an vibration signal

What is the new period if the pendulum is taken to a planet that has 4 times the mass and 4 times the radius of earth

Answers

The new period of the pendulum when it is taken to the new planet is  double of its period on Earth.

Period of a pendulum

The period of a pendulum is given by the following formula;

[tex]T = 2\pi \sqrt{\frac{l}{g} }[/tex]

where;

g is acceleration due to gravity of the pendulumL is length of the pendulumAcceleration due to gravity of the new planet

The acceleration due to gravity of the new planet is calculated as follows;

[tex]g_E = \frac{GM_E}{R_E^2} = 9.81 \ m/s^2 \\\\g(new \ planet) = \frac{G(4M_E)}{(4R_E)^2} = \frac{4GM_E}{16R_E^2} = \frac{GM_E}{4R_E^2} = \frac{9.81}{4} = 2.45 \ m/s^2[/tex]

New period of the pendulum

[tex]T = 2\pi \sqrt{\frac{l}{g} } \\\\T =\frac{2\pi \sqrt{l} }{\sqrt{g} } \\\\T_1\sqrt{g_1} = T_2\sqrt{g_2} \\\\T_E\sqrt{g_E} = T\sqrt{g} \\\\T = \frac{T_E\sqrt{g_E}}{\sqrt{g} } \\\\T = \frac{T_E \times \sqrt{9.81} }{\sqrt{2.45} } \\\\T = 2T_E[/tex]

Thus, the new period of the pendulum when it is taken to the new planet is double of its period on Earth.

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The vertebral region is _________ to the scapular region.

Answers

Answer:

The answer is medial!

Explanation:

The vertebral region is medial to the scapula.

Hope This Helps!

-Justin:)

Hello people ~
Sound cannot travel through
(a) air
(b) water
(c) air
(d) vacuum​

Answers

Answer:

Vaccum

Explanation:

Sound travels through the particles of different matter In vaccum there is no air so no matter and so no particles .So sound can't travel through vaccum.

You can test it .

Take a speaker and keep it inside a bottle ,close it .You won't hear any sound

A garbage can of mass 12 kg standing on horizontal ground is pushed by a horizontal force of 40N. If the coefficient of static friction is 0. 32 and the coefficient of dynamic or

kinetic friction is 0. 24 between the can and ground, the acceleration of the garbage can is

____ m/s2

Answers

The acceleration of the garbage can is 2.55 m/s².

What is acceleration?

Acceleration is the rate of change of velocity with respect to time.

To calculate the acceleration of the can, we use the formula below

Formula:

ma = F-mg(η-μ)............ Equation 1

Where:

F = Horizontal forcem = mass of the cang = acceleration due to gravitya = acceleration of the canμ = Coefficient of static frictionη = Coefficient of kinetic friction

Make a the subject of the equation

a = [F-mg(η-μ)]/m.................. Equation 2

From the question,

Given:

F = 40 Nm = 12 kgg = 9.8 m/s²μ = 0.32η = 0.24

Substitute these values into equation 2

a = [40-12×9.8(0.32-0.24)]/12a = (40-9.408)/12a = 30.592/12a = 2.55 m/s²

Hence, the acceleration of the garbage can is 2.55 m/s².

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how do the properties of waves correspond with observations of waves?

Answers

Answer:

no sabo por q no mi entender

Why doesn't mercury have an atmosphere?

Answers

First mercury is small and does not have much gravity so it is hard to hold on to atmosphere . Second mercury is close to the sun .

Answer:

 The main reasons are two. Mercury's atmosphere is hard to hold onto because it is small and does not have much gravity. As Mercury is close to the Sun, any atmosphere is blasted away by material being blown off the Sun.

Hope this helps friend!

When an object standing on the floor is tipped, the height of its center of gravity (cg) may or may not change. Classify each case as stable, unstable, or neutral

Answers

The three types of equilibrium in an object are;  stable, unstable, or neutral equilibrium.

What is equilibrium?

The term equilibrium refers to a situation in which all the forces acting on an object are balanced such that the object does not move. The question is incomplete as the images are missing.

There are three types of equilibrium:

Stable equilibrium: In a stable equilibrium, the object returns to rest in its original place when displlaced.Unstable equilibrium: In this type of equilibrium, the body moves further away from its original position when displaced.Neutral equilibrium: In this type of equilibrium, the object comes to rest in a new position when displaced.

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When an object standing on the floor is tipped, the height of its center of gravity (cg) for each case as stable, unstable, or neutral may increase, decreased and remain same respectively.

What is the equilibrium state of a standing object?

Equilibrium is the location of the body, in which the body be static or in motion and does not change it with respect to time.

The equilibrium of an object can be classified in the 3 following types.

Stable Equilibrium- Stable equilibrium is the condition, in which the object gains its position back after displacing it.Unstable Equilibrium-Unstable equilibrium is the condition, in which the object does not gain its position back after displacing it.Neutral Equilibrium-Natural equilibrium is the condition, in which the object displace from its position and there is no force acting on it.

When an object standing on the floor is tipped, the height of its center of gravity (cg) may or may not change.

The stability of object demands in the center of gravity. Lower the value of CG, results in more stable object. For each case,

Stable-Center of gravity is increased when tipped.Unstable-Center of gravity is decreased when tipped.Natural-Center of gravity is remained at same level when tipped.

Thus, when an object standing on the floor is tipped, the height of its center of gravity (cg) for each case as stable, unstable, or neutral may increase, decreased and remain same respectively.

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angular velocity of a rotating wheel increases 2 rev/s every minute. The angular acceleration of this wheel is:

Answers

The angular acceleration of the rotating wheel at the given rate of change of angular velocity is 0.21 rad/s².

Angular acceleration of the wheel

The angular acceleration of an object is the rate of change of anguar velocity of the object with time.

[tex]\alpha = \frac{\Delta \omega }{\Delta t}[/tex]

where;

Δω is the change in the angular velocityΔt is the change in time

Change in angular velocity of the wheel is calculated as follows;

[tex]\Delta \omega = 2 \ \frac{rev}{s} \times \frac{2\pi \ rad}{1 \ rev} = 4\pi \ rad/s = 12.57 \ rad/s[/tex]

Change in time, Δt = 1 min = 60 s

The angular acceleration of the rotating wheel is calculated as follows;

α = (12.57) / (60)

α = 0.21 rad/s²

Thus, the angular acceleration of the rotating wheel at the given rate of change of angular velocity is 0.21 rad/s².

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2 eggs cook in a frying pan, which is sitting over a gas burner. Is thermal energy being transferred from the metal pan to the eggs by radiation in this image? Why or why not?

Answers

Hope that helps have a good day though.

Answer:

No, the eggs are in direct contact with the metal pan, which is in direct contact with the gas flame, so this is conduction, not radiation

Reasons:
-Thermal energy is being transferred by conduction.

-Radiation transfers thermal energy by electromagnetic waves.

-Radiation does not transfer thermal energy by direct contact.

Radiation heat transfer is a process where heatwaves are emitted that may be absorbed, reflected, or transmitted through a colder "body". Sun heats the earth by electromagnetic waves. The sun does not come in physical contact with the Earth to transfer heat. (In my opinion, the Earth touching the sun would not be on my to-do list.)



Explanation:

Have a great rest of your day
#TheWizzer

The earliest stage of a star’s life before it begins to undergo fusion is known as:

Answers

Answer:

A protostar is the earliest stage of a star's life. A star is born when the gas and dust from a nebula become so hot that nuclear fusion starts.

The origin of star is called nebula. The earliest stage of a star’s life before it begins to undergo fusion is known as a protostar.

What is the earlier stage of star ?

Every star begins from nebula. A nebula is a huge gas and dust cloud. Some of the gas and dust in a nebula can be drawn together by gravity. The cloud's contraction is then described as a protostar. The first stage of a star's life is called a protostar.

As the gas and dust from a nebula heat up to a point where nuclear fusion begins, a star is created. A star is referred to as a main sequence star once it has "switched on". A main sequence star turns into a red giant or a red super giant when its hydrogen fuel runs exhausted.

An exploding red super massive star is possible. It is referred to be a supernova. After the star explodes, some of the ingredients from the star are left behind. Hence, the earlier stage of a star before fusion starts is called a protostar.

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