in which of the following conditions would a person NOT hear an echo!100 points to the first correct awnser

Answers

Answer 1

Answer:

Umm well a person can not hear when a  it snows or maybe like a snow storm

Explanation: snow is so light you dont hear it land but you can see it

Answer 2

Answer: the answer is, A sound wave reaches the ear, and the reflected wave reaches the ear less than 0.1 seconds later

Explanation: PENN


Related Questions

Fluorescent lamp of 25W gives more light than the filament lamp of 50W. Why?​

Answers

Answer:

Fluorescent lamp releases more light energy.

Explanation:

This is so because the fluorescent lamp releases more light energy and less heat energy than that of a filament lamp with the same rating.

Fluorescent lamp releases more light energy than that of filament lamp and also less heat energy than that of a filament lamp.

What is Power of fluorescent lamp and filament lamp?

The filament and the fluorescent lamps are two different types of most commonly used light lamps. The filament lamps are the lamps which work on the phenomenon of incandescent whereas a high resistance filament is heated up in the lamp until it radiates visible light energy. Whereas, a fluorescent lamp is the lamp which works by ionizing a gas that emits photons or energy particles.

The fluorescent lamp releases more light energy and less heat energy than that of a typical filament lamp with the less power of 25W than 50W.

Learn more about Fluorescent lamp here:

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#SPJ2

In the past, most children who went sledding in the winter snow in Verland used wooden sleds with runners and steering bars. Ten years ago, smooth plastic sleds became popular; they go faster than wooden sleds but are harder to steer and slow. The concern that plastic sleds are more dangerous is clearly borne out by the fact that the number of children injured while sledding was much higher last winter than it was ten years ago.

Which of the following, if true in Verland, most seriously undermines the force of the evidence cited?
(A) A few children still use traditional wooden sleds.
(B) Very few children wear any kind of protective gear, such as helmets, while sledding.
(C) Plastic sleds can be used in a much wider variety of snow conditions than wooden sleds can.
(D) Most sledding injuries occur when a sled collides with a tree, a rock, or another sled.
(E) Because the traditional wooden sled can carry more than one rider, an accident involving a wooden sled can result in several children being injured.

Answers

Answer:

(E) it seems like the best option

Is energy conserved during a fission/fusion reaction?

Answers

Answer:

No,but it can be changed into other forms.

between the continental shelf and a continental rise?

volcanic island

seamount

continental slope

Answers

Answer:

continental slope

Explanation:

the continental shelf is after the land and before the continental rise as it's in the diagram of an ocean floor

Colulate the wavelength of i)a ball moving of 40m/s i i)A proton moving at 40 ms i i i) An election moving at 40m/s​

Answers

Explanation:

[tex]thank \: you[/tex]

How are the oscillating magnetic and electric fields of an electromagnetic wave positioned relative to each other?​

Answers

Answer:

Electromagnetic waves consist of both electric and magnetic field waves. These waves oscillate in perpendicular planes with respect to each other, and are in phase. The creation of all electromagnetic waves begins with an oscillating charged particle, which creates oscillating electric and magnetic fields.

Explanation:

what is a risky behaviour​

Answers

Explanation:

Doing homework is risky behaviour broo

taking credit of someone else’s work.

Calculate the electrical energy transferred by a 60W electric bulb that is turned on for 20s and 5minutes.

Answers

Answer:

approximately 0.00504 kWh

Explanation:

This electrical energy and is measured in kWh.

For 5 minutes and 20 seconds of use, it is 0.06 W x 0.084 h = 0.00504 kWh.

Note: 60W = 0.06kW; 5min 20sec = 0.083(8) ≈ 0.084 hour

What is concentration gradient?​

Answers

Answer:

The difference in the concentration of a substance between two areas is called the concentration gradient . The bigger the difference, the steeper the concentration gradient and the faster the molecules of a substance will diffuse. The direction of diffusion is said to be 'down' or 'with' the concentration gradient.

Explanation:

1. Alice decides to measure the density of the banana.

a)What equipment will she need to measure it?

b)Explain how she could use that equipment to measure the density.​

Answers

Answer:

A) Measuring cup with water and a scale

Explanation:

Fill the measuring cup with water to a certain point, and record the current height of the water. After placing the banana fully into the water, record the new height of the water. Subtract the old height from the new height. Now you have the banana's volume.

Then, place the banana on a scale to get it's mass.

Perform [tex]\rho ={\frac {m}{V}}[/tex], where p = density, m = mass, v = volume.

Note: 1 milliliter = 1 centimeter^3

a sound intensity of 70 dB is observed a distance of d from the source of sound. what sound intensity would be observed at a distance 2d from the source

Answers

Answer:

Correct option is

B

16dB

Sound level at A is ⊥o⊥B

If the intensity of sound at A 4 cm away from the source is I

A

then.

⊥o=10log

I

o

I

A

Where I

o

=10

−12

w m

−2

⇒⊥=log

10

−12

I

A

10

−12

I

A

=10

⇒I

A

=10

−11

wm

−2

If the source (s) is emmitting the sound energy of power P

I

A

=

4×(4)

2

P

⇒P=10

−11

×64π w

⇒ Intensity of sound (I

B

) ar point B,2 m

I

B

=

4π(2)

2

P

I

B

=

16π

64π×10

−11

10 m

−2

⇒I

B

=4×10

−11

wm

−2

⇒ Sound level at 2m=10log(

I

I

B )

=10log(10 −12

4×10 −11)

=10log40

=16.02

Hence Sound level at 2m from sourceis 16 dB

Lilly drove her car east for a total of 6 hours at a constant velocity. In one-third of that time, she drove 160 kilometers. What was her velocity?
Write your answer as a whole number.

Answers

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Answer: 160 km

Explanation:

maize is called monocot why?​

Answers

Answer:

Rice, wheat, maize all have one cotyledon in their seed, so they are monocots. Explanation: The monocot plants have a single cotyledon. They have a fibrous root system, leaves in monocots have parallel venation.

Explanation:

need help asap!! thank you in advance, will mark brainliest!!

Answers

Answer:

Wanna be my friend?

Explanation:

How are the oscillating magnetic and electric fields of an electromagnetic wave positioned relative to each other?​
A) They are parallel to each other.
B) The magnetic field is rotated 45° from the electric field
C) the electric field is rotated 45° from the magnetic field.
D) They are perpendicular to each other​

Answers

Answer:

D.

for the scalar product between two vectors to be 0 either one of thm is zero vector or they are perpendicular to each other


1. What distances can you be certain of on the ruler in Model 1?

Answers

Answer:

Zero cm and 10 cm......

if my answer helps you than mark me as brainliest

plz hep me tell ans of this only​

Answers

We have no idea what force the object might exert until it hits something.

In order to accelerate 70 kg at the rate of 20 m/s^2, YOU or some machine has to PUSH it with a force of (F=m•a) 1,400 Newtons. If you stop pushing it, it stops accelerating.

A car accelerates by 4 m/s^2 and travels for 2.5 mins with an initial velocity of 20m/s. Find the final velocity.

Answers

Answer:

540m/s

Explanation:

v= u + at

u change t to seconds

Difference between Work against gravity and Work done against friction?​

Answers

Answer:

if there is not motion produced in body, the works become zero. We can do work against gravity or against friction. when we lift something then it is work done against gravity and when we slide something then it is work done against friction.

I hope u like it pls follow me

Ice has a density of 0.92 g/cm°; gasoline has a density of 0.68 g/cms. Will ice float in gasoline? Why or why
not?

Answers

Answer:

No,ice will not float

Explanation:

A substance sinks in another if it has a greater density than the other substance. The density of ice is clearly greater here and so ice will sink

Explain a lever and a pivot in a full sentence​

Answers

Answer:

The lever is a movable bar that pivots on a fulcrum attached to a fixed point. The lever operates by applying forces at different distances from the fulcrum, or a pivot. As the lever rotates around the fulcrum, points farther from this pivot move faster than points closer to the pivot.

IF HELPED MARK AS BRAINLIEST

Two representative elements are in the same period of the periodic table. Which statement correctly describes the atoms of the two elements?(1 point)
They have the same number of valence electrons.
They have the same number of valence electrons.

They have valence electrons in different energy levels.
They have valence electrons in different energy levels.

They have valence electrons in the same energy level.
They have valence electrons in the same energy level.

They have the same number of electrons.Helium is in group 18 of the periodic table. How is helium different from the other elements in this group?(1 point)Helium atoms have valence electrons in the first energy level, while atoms of the other elements in the group have valence electrons in the second energy level.
Helium atoms have valence electrons in the first energy level, while atoms of the other elements in the group have valence electrons in the second energy level.

Helium atoms have 2 valence electrons, while atoms of the other elements in the group all have 8 valence electrons.
Helium atoms have 2 valence electrons, while atoms of the other elements in the group all have 8 valence electrons.

Helium atoms have a full outer energy level, while atoms of the other elements in the group do not have a full outer energy level.
Helium atoms have a full outer energy level, while atoms of the other elements in the group do not have a full outer energy level.

Helium atoms have 2 electrons, while atoms of the other elements in the group all have 18 electrons.
Use the periodic table to answer the question.
Which element has atoms with valence electrons in a higher energy level than those of calcium (Ca)?
lithium (Li)
lithium (Li)

cesium (Cs)


bromine (Br)

oxygen (O)
Use the periodic table to answer the question.
Which statement best describes the arrangement of electrons in an atom of fluorine (F)?
There are seven electrons in the first energy level and two electrons in the second energy level.
There are seven electrons in the first energy level and two electrons in the second energy level.

There are five electrons in the first energy level and two electrons in the second energy level.
There are five electrons in the first energy level and two electrons in the second energy level.

There are two electrons in the first energy level and seven electrons in the second energy level.
There are two electrons in the first energy level and seven electrons in the second energy level.

There are two electrons in the first energy level and five electrons in the second energy level.

Answers

1) They have valence electrons in the same energy level.

2) Helium atoms have 2 valence electrons, while atoms of the other elements in the group all have 8 valence electrons.

3) cesium (Cs)

4) There are two electrons in the first energy level and seven electrons in the second energy level.

In the periodic table, elements are arranged in order of increasing atomic number into groups and periods.

In the periodic table, we have an arrangement of atoms based on their respective groups and periods.

If I pick two representative elements in the same period, their number of valence electrons will differ by 1 but they will all be accommodated in the same energy level.

Helium is the first member of group 18. Unlike the other members of the group, its first shell is also its valence shell. It has two and not eight valence electrons like other members of the group.

The electronic configuration of Ca is [Ar] 4s², that of Li is [He] 2s1, that of Cs is [Xe] 6s1, that of Br is [Ar] 4s² 3d¹⁰ 4p⁵ and that of oxygen is [He] 2s² 2p⁴.

We can see that only Cs has  valence electrons in higher energy orbitals than those of Ca.

Lastly, Fluorine is in group 17. There are nine electrons in this atoms. They arranged in such a way that there are two electrons in the first shell and seven electrons in the second shell.

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show with the help of an experiment that the acceleration of a freely falling body doesn't depend on the mass of that body. pls answer this question:)

Answers

Answer:

Experiment

Materials needed

Stop watch, a small stone, a big stone, a balance.

Procedure

Measure the mass of the two stones.

Hold the two stones about 5m above the ground level.

Drop the stones simultaneously.

Record the time taken for the stones to strike the ground.

Repeat the procedure with different masses of objects at the same height.

Observation, it will be observed that, all the objects dropped from the same height strike the ground at the same time interval.

Conclusion; a falling object doesn't depend on mass

Explanation:

½mv²=mgh

g=½(V²/h)

When an object is held at a height, it posses gravitational potential energy which is mgh, where m= mass, h=height, g=acceleration due gravity

When the object is dropped, the potential energy will be converted to kinetic energy which is ½mv², where V=velocity at which the object moves.

V=∆h/t, ∆h is change in height with respect to time.

½mv²=mgh

Mass cancel out,

g=v²/2h

This implies that g does not depend or is not affected by mass. Hence heavy object and light object will reach the ground at the same time when dropped from the same height. When air resistance is negligible.

can you convert liters to kilometers explain ur answer plsss

Answers

Answer:

Yes we can.

Explanation:

1 Litre= 0.001km

1000 Litre= 1km

A stone of mass 600g is thrown vertically upwards. calculate the value of the gravitational force on the stone at its highest point. take g = 10N/kg​

Answers

Answer:

6N

Explanation:

F = m × g

= 0.6 × 10

= 6N

to find the force you first have to convert the mass to kg by dividing 600 by 1000 giving you 0.6

then you can multiply the mass times the gravity giving you a gravitational force of 6N

A still object has a mass of 25kg, what would be the Weight? What would be the Normal Force?​

Answers

Mass=25kgAcceleration due to gravity=10m/s^2

[tex]\\ \rm\longmapsto Force=Mass(Acceleration)[/tex]

[tex]\\ \rm\longmapsto Force=25(10)[/tex]

[tex]\\ \rm\longmapsto Force=250N[/tex]

SCIENCE
A student wants to try to convince her parents to stop serving peas for dinner. She lays out her argument that peas are high in fructose, which is a type of sugar. Which test could she use to provide scientific evidence to support her argument that peas are high in fructose?(1 point)

brown paper bag test
vinegar test
Benedict’s test
iodine test

Answers

Answer:Benedict’s Test

Explanation:

The student will use Benedict's test to support her argument.

The common reagents for testing carbohydrates are iodine and Benedicts test.

While iodine gives a positive result with starch, it doesn't react with fructose.

Benedict's reagent is used to determine the presence of reducing sugar in a given solution.

A positive test with Benedict's reagent is determined by a color change from clear blue to brick-red with a precipitate.

A reaction between fructose and Benedict's solution gives a positive test from the color change which occurs when the fructose is reduced to simple sugar such as glucose and mannose.

Thus, the student will use Benedict's test to support her argument.

Learn more here:https://brainly.com/question/13397926

NEED HELP ASAP What are the lengths of the x and y components of this vector?

Answers

Explanation:

the lengths of the x and y components of the vector :

the x- Component:

Vx = 12×cos72° = 12× 0.3090 = 3.708

the y-component:

Vy = 12×sin72° = 12× 0.9510 = 11.412

~Trigonometry

-

x-component

= 12 . cos 72

= 12 . 0,3090

= 3,708

y component

= 12 . sin 75

= 12 . 0,9510

= 11,412

#mathisfun


A student conducts an experiment to determine how the amount of water given to a plant affects its growth.

What is the dependent variable for this experiment?
a. the amount of water
b. the height of the plant
C. the amount of sunlight
d. the amount of soil

Answers

Answer:

Option A because the researcher can change the amount of water given to the plant to determine the dependent factor, how much the plant grows. Options C and D are both control variables that need to stay the same in order to perform this experiment correctly.

the power of a bulb is 100 watt .what does it mean​

Answers

Answer:

Explanation: 100 watts is a unit of power.

A watt is also the amount of energy being consumed. So the more watts the brighter the light bulb is lit.

Other Questions
Hello!Im beginning year 11 this year and I recently did really bad in my Mocks! I really need some help and advice for all of my subjects because I truly dont know how to revise effectively and because I keep Procrastinating! Any advice would be appreciated or if u have links to videos and helpful websites I would appreciate it Here are my results :Maths : 4Eng Language : 4 Eng Lit : 4Chemistry : 4Physics : 3Biology : 3RE: 4Health and Social care : Level 2 PassHistory : 4 Food Tech : 4Spanish : 4 Thank u! Which describes a relationship when calculating the energy of a photon? The energy of the photon is directly proportional to frequency. The energy of the photon is inversely proportional to frequency. As the energy of the photon increases, Plancks constant increases. As the energy of the photon increases, Plancks constant decreases. 1. A car starts from rest and accelerates uniformly for 8.0 s. It reaches a final speed of 15ms1a. What is the acceleration of the car?b. What is the average velocity of the car?C. Calculate the distance travelled by the car. Reduce the Fraction 15----30 1. Here is an equation that represents a function: 72x +12y = 60. Select all the different equations that describe the same function: A. 120y + 720x = 600 B. y = 5 - 6x C. 2y + 12x = 10 D. y=5 + 6x E. x= 5/6 - y/6 F. 7x + 2y = 6 G. x = 5/6 + 5/6 birinci ve ikinci inonu savaslari nasil gerceklesti The square below represents a unit or a whole. What fraction is represented by the PLZ HELP WILL MARK BRAINLIEST! Each molecule of ammonia (NH3) is made up of one nitrogen atom and three hydrogen atoms. Which term best describes ammonia?A. heterogeneous mixtureB. elementC. homogeneous mixtureD. compound 6. Answer the following questions in short. a. How does carbon dioxide enter the plant? b. Explain the term heterotrophic nutrition. c. Name the two types of decomposers. d. List the materials necessary for photosynthesis. 13 name the political leader who persecuted jews in germany During the grand opening of an electronics store, any customer has a 17% chance of winning a free laptop. What is the chance that a customer does not win a free laptop? 81% 83% 51% 37% how to understand hypabolic equations ( Instrucciones Averigua el mensaje escondido al marcar las oraciones que usan el presente. Your friend has written you a message hidden in a note. Find out what it is). " Read Note Now" ------> Estudio en la biblioteca todos los das. Espero sacar buenas notas. Or para que mi mam se recupere. Ella nos cuid mucho. Quiero ganar la competencia de ciencias. Gan muchos premios el otro da. Bailar en el auditorio de la escuela. Paso muchas horas estudiando. Invit a un amigo al baile de la escuela. Estudias conmigo? No me gust practicar por tantas horas.--------> ( Find the true message by marking out any sentences that are in the present tense). Will Mark Brainliest What does a food chain show?"why plant and animal matter break downO where resources are found in a habitatO how producers use sunlight to make food energyO how living things depend on each other for food Answer 9 10 11 please Answer this question. An elevator was on the 23rd floor. Itthen went down 7 floors and thenanother 4 floors. What floor was theelevator on now? Convert 50 kilograms into grams.show your work Simplify show step by step 30 POINTS!