Hi :) how to do this?

Answer:

Explanation:

The speed of sound is very high . It is about 340 m /s . In one echo , it takes approximately

2 x 100 / 340

= .6 sec

In 10 simultaneous echo , it will take 6 s . It is difficult to measure .6 sec but to measure 6 s is easy and it can be made with greater precision , so we can calculate velocity of sound with great precision .

This is the reason why , instead of one echo , 10 echos are made and duration of 10 echo is measured , rather than making one echo and measuring time of one echo .  

Answer:

Explanation:it is too easy

Answer:

The correct option is;

D: Its vibrations are not transmitted to the moon's atmosphere

Explanation:

A tuning fork is used to produce sound by vibration  such that the tune produced is pure

The tune, sound, produced by the tuning fork is transmitted as sound wave through the air by means of the gases of the air as a transmission medium so people at a distance that have air around them can hear the tuning fork sound

On the Moon's surface, the atmosphere is very and it is referred to technically as an exosphere, so the sound of the tuning fork has no medium through which to transmit and therefore, it is not transmitted on the Moon's atmosphere.

Answer:

The correct option is;

The proposal is denied, because participants will likely suffer psychological harm

Explanation:

Among the recommendations in the report on ethical research with children, it is suggested that the following should be observed by researchers;

1) Seeking consent should be a continuous process

2) Contemplate payment forms other than money to allow more discretion on child safety

3) Have two way communication with the child

4) Ask for assent of the child participating in the research

The above APA suggestions where not met by the researcher in the study.

Answer:

The proposal is denied, because participants will likely suffer psychological harm.

Explanation:

This proposal would cause psychological harm to its participents.

I also took the test and that was the correct answer.

Answer:

Hay diversas leyes que podemos usar acá.

Acá sabemos que la vejiga aumenta su tamaño al reducir la presión, esto tiene sentido, pues al haber menos presión, hay menos fuerza que comprime la vejiga, lo que le permite aumentar su volumen.

Acá tenemos una relación inversa de la forma: V = K/P

Una relación inversa donde la presión esta en el denominador y K es un termino que no depende ni del volumen ni de la presión.

Entonces, a medida que aumenta P, el denominador aumenta, por lo que el valor del volumen decrece.

Un ejemplo de una ecuación similar es la del gas ideal, por ejemplo, para un gas ideal dentro de un globo de volumen V para una dada presión P:

V = nRT/P

donde n es el numero de moles, R es la constante termodinámica y T es la temperatura, acá podemos ver que esta ecuación tiene la misma forma fundamental que la escrita arriba.

Answer: D

Explanation:

Given that a car travels from point A to B in 3 hours and returns back to point A in 5 hours. Points A and B are 150 miles apart along a straight highway.

From point A to B

The speed = distance / time

Where

Distance = 150 mile

Time = 3 hours

Substitute the values into the formula

Speed = 150/3 = 50 mile/ hours

From Point B to Point A

Distance = 150 miles

Time = 5 hours

Where speed = distance/ time

substitute all the parameters into the formula

Speed = 150/5 = 30 mph

Therefore, The car travels at 50 mph for the first half and 30 mph for the second half.

The correct answer is option D

If you are talking about mecury as in a chemical element than it is: Hg

If you are talking about the planet Mercury than: The symbol for Mercury represents the head and winged cap of Mercury, god of commerce and communication, surmounting his caduceus (staff). The symbol for Venus is designated as the female symbol, thought to be the stylized representation of the hand mirror of this goddess of love.

Answer:

The symbol of mercury is....

Hydrargyrum ( Hg )

Hope this helps......

Pls mark my ans as brainliest

Answer:

The final temperature is 31.94°

Explanation:

The mass of the water in the container m₁ = 200 g = 0.2 kg

The initial temperature of the water,  T₁₁ = 30°C

The mass of the iron, m₂ = 200 g = 0.2 kg

The temperature of the iron T₂₁= 50°C is immersed in the water,

The specific heat capacity of the water, c₁ = 4200 J/(kg·°C)

The specific heat capacity of the iron, c₂ = 450 J/(kg·°C)

Heat capacity relation is given by the formula;

Heat capacity Q = Mass, m × Specific heat capacity, c × Temperature change, (T₂ - T₁)

Given that energy can neither be created nor destroyed, and with the assumption that all the heat lost by the nail is gained by the water we have;

Heat lost by iron nail = Heat gained by the  water

m₁ × c₁ × (T₂ - T₁₁) = m₂ × c₂ × (T₂₁ - T₂)

Where, T₂ is the final temperature

0.2 kg × 4200 J/(kg·°C) × (T₂ - 30) = 0.2 kg × 450 J/(kg·°C) × (50° - T₂)

840·T₂ - 25200 = 4500 - 90·T₂

4500 + 25200 = 840·T₂ + 90·T₂

29700 = 930·T₂

T₂ = 29700/930 = 31.94°.

The final temperature = 31.94°.

Answer:

[tex]\Large \boxed{\mathrm{5.67 \ seconds }}[/tex]

Explanation:

[tex]\displaystyle \mathrm{acceleration \ = \ \frac{final \ velocity - initial \ velocity }{elapsed \ time}}[/tex]

[tex]\displaystyle A \ = \ \frac{V_f - V_i }{t}[/tex]

[tex]\displaystyle 3 \ = \ \frac{25 - 8 }{t}[/tex]

[tex]\displaystyle 3 \ = \ \frac{17 }{t}[/tex]

[tex]\displaystyle t \ = \ \frac{17 }{3} \approx 5.67[/tex]

Answer: 19 meters.

Explanation:

We want to find the total displacement between t = 2s and t = 4s.

To do it, we can integrate our function, first write our velocity equation.

for t ≤ 3s, we have a linear equation, let's write it:

A linear relationship can be written as:

y = a*t + b

where a is the slope and b is the y-axis intercept.

For a line that passes through the points (x1, y1) and (x2, y2), the slope can be written as:

a = (y2 - y1)/(x2 - x1).

Now we can see that our line passes through the points (1, 0) and (0, -2)

then the slope is:

a = (0 -(-2)/(1 - 0) = 2/1 = 2

and knowing that when t = 0s, v(0s) = -2m/s, then our equation is:

v(t) = (2m/s^2)*t - 2m/s for t ≤ 3s

now, for t ≥3s the equation is constant, v(t) = 4m/s.

then we have

v(t) = (2m/s^2)*t - 2m/s -------if t ≤ 3s

v(t) = 4m/s ----- if t ≥ 3s

Now we integrate over time to get the position:

for t ≤ 3s we have:

p(t) = (1/2)*(2m/s^2)*t^2 - 2m/s*t + C

where C is a constant of integration, as we are calculating the displacement  this constant actually does not matter, so we can use C = 0m

p(t) = (1m/s^2)*t^2 - 2m/s*t  for t ≤ 3s

and p(3s) =  (1m/s^2)*3s^2 - 2m/s*3s = 9m - 6m = 3m is the initial position of the other part of the function.

for t ≥ 3s we have:

p(t) = 4m/s*t + p(3s) = 4m/s*t + 3m

then the position equation is:

p(t) = (1m/s^2)*t^2 - 2m/s*t  ---- t ≤ 3s

p(t) = 4m/s*t + 3m --- if t ≥ 3s

Now the displacement will be:

p(4s) - p(2s) where for each time, you need to use the correct function:

p(4s) = 4m/s*4s + 3m = 16m + 3m = 19m

p(2s) =  (1m/s^2)*2s^2 - 2m/s*2s = 4m - 4m = 0m

p(4s) - p(2s) = 19m - 0m = 19m

The butterfly displacement x from t=2 to 4s is 19 meters.

The spacing between two specified points is represented by the one-dimensional quantity of displacement (symbolised as d or s), commonly known as length or distance.

The total displacement between t = 2s and t = 4s.

Integrate our function, the velocity equation.

for t ≤ 3s, we have a linear equation, let's write it:

A linear relationship can be written as:

y = a x t + b

where a is the slope and b is the y-axis intercept.

For a line that passes through the points (x1, y1) and (x2, y2), the slope can be written as:

a = (y2 - y1)/(x2 - x1).

The line passes through the points (1, 0) and (0, -2)

The slope is:

a = (0 -(-2)/(1 - 0) = 2/1 = 2

When t = 0s, v(0s) = -2m/s, then our equation is:

v(t) = (2m/s²) x t - 2m/s for t ≤ 3s

now, for t ≥3s the equation is constant, v(t) = 4m/s.

v(t) = (2m/s²) x t - 2m/s -------if t ≤ 3s

v(t) = 4m/s ----- if t ≥ 3s

Now we integrate over time to get the position:

for t ≤ 3s we have:

p(t) = (1/2) x (2m/s²) x t^2 - 2m/s x t + C

where C is a constant of integration, to calculate the displacement  this constant actually does not matter,

p(t) = (1m/s²)*t^2 - 2m/s x t  for t ≤ 3s

and p(3s) =  (1m/s^2) x 3s² - 2m/s x 3s = 9m - 6m = 3m is the initial position of the other part of the function.

for t ≥ 3s we have:

p(t) = 4m/s x t + p(3s) = 4m/s x t + 3m

then the position equation is:

p(t) = (1m/s^2) x t² - 2m/s x t  ---- t ≤ 3s

p(t) = 4m/s x t + 3m --- if t ≥ 3s

Now the displacement will be:

p(4s) - p(2s) where for each time, you need to use the correct function:

p(4s) = 4m/s x 4s + 3m = 16m + 3m = 19m

p(2s) =  (1m/s²) x 2s²- 2m/s x 2s = 4m - 4m = 0m

p(4s) - p(2s) = 19m - 0m = 19m

Thus, the displacement is 19 m.

To learn more about displacement, refer to the link:
https://brainly.com/question/11934397

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Answer:

17.15 m

Explanation:

Assuming the well is empty (full of air instead of water), the speed of sound is v = 343 m/s.

The water well acts as a pipe closed at one end.  Therefore, the depth of the water well must be an odd multiple of a quarter of the resonant wavelength.

L = (2n − 1) λ/4, n = 1, 2, 3, etc.

v = λf, so λ = v/f.  Substituting:

L = (2n − 1) v/(4f)

Solving for frequency:

f = (2n − 1) v/(4L)

The difference between two successive resonant frequencies is therefore:

Δf = (2(n+1) − 1) v/(4L) − (2n − 1) v/(4L)

Δf = (2n + 1) v/(4L) − (2n − 1) v/(4L)

Δf = 2 v/(4L)

Δf = v/(2L)

Plugging in values:

50 Hz − 40 Hz = 343 m/s / (2L)

2L = 34.3 m

L = 17.15 m

Answer:

[tex] \boxed{\sf Acceleration \ (a) = 2 \ m/s^{2}} [/tex]

[tex] \boxed{\sf Distance \ covered \ (s) = 100 \ m} [/tex]

Given:

Initial velocity (u) = 0 m/s

Final velocity (v) = 20 m/s

Time taken (t) = 10 sec

To Find:

(i) Acceleration (a)

(ii) Distance covered (s)

Explanation:

[tex]\sf (i) \ From \ 1^{st} \ equation \ of \ motion:[/tex]

[tex] \sf \implies v = u + at[/tex]

[tex] \sf \implies 20 = 0 + a(10)[/tex]

[tex] \sf \implies 10a = 20[/tex]

[tex] \sf \implies \frac{10a}{10} = \frac{20}{10} [/tex]

[tex] \sf \implies a = 2 \: m/ {s}^{2} [/tex]

[tex]\sf (ii) \ From \ 2^{nd} \ equation \ of \ motion:[/tex]

[tex] \sf \implies s = ut + \frac{1}{2} a {t}^{2} [/tex]

[tex]\sf \implies s = (0)(10) + \frac{1}{2} \times 2 \times {(10)}^{2} [/tex]

[tex]\sf \implies s = \frac{1}{ \cancel{2}} \times \cancel{2} \times {(10)}^{2} [/tex]

[tex]\sf \implies s = {10}^{2} [/tex]

[tex]\sf \implies s = 100 \: m[/tex]

Answer:

the force applied to restore a spring to its original length

Explanation:

Explanation:

Assuming the 10 m distance is the vertical displacement, the work done by both people is the same.

Work = force × distance

W = (250 N) (10 m)

W = 2500 J

The power of the first person is:

Power = work / time

P = 2500 J / 120 s

P = 20.83 W

The power of the second person is:

P = 2500 J / 60 s

P = 41.67 W

Answer:

The percentage error in quantity P is 19%.

Explanation:

It is given that,

A physical quantity P is related to four observables a, b and c as follows:

[tex]P=\dfrac{a^3b^2}{c^4}[/tex]

The percentage errors of measurements in a, b and c are 1%, 4% and 2% respectively.

We need to find the percentage error in quantity P. It is given by :

[tex]\dfrac{\Delta P}{P}\times 100=(3\times \dfrac{\Delta a}{a}+2\times \dfrac{\Delta b}{b}+4\times \dfrac{\Delta c}{c})\\\\=3\times 1+2\times 4+4\times 2\\\\\dfrac{\Delta P}{P}\times 100=19\%[/tex]

So, the percentage error in quantity P is 19%.

Oil is optically denser than water. When sound/light goes from optically denser medium to optically rarer medium, their velocity increase and they moves away for normal.

The sound wave speeds up and bends

[tex] \Large{ \underline{ \boxed{ \pink{ \bf{Option \: (D)}}}}}[/tex]

As, In optics we learnt that light undergoes refraction when travels from medium of different densities. Similarly, Sound also follows the law of refraction.

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Answer:

the sound wave slows down and bends

Explanation:

a p e x

Answer:

c

Explanation:

The marginal cost curve image  has been attached from which we can clearly, indicate that

ATC = average total cost

AFC = average fixed cost

AVC = average variable cost.

From the graph we can indicate that the marginal cost curve

(c) Lies above the AVC curve when the AVC curve slopes downward.

Answer:

66.86m

Explanation:

Velocity of ball thrown, u = 23.5 m/s

Initial height of the ball above the water, H = 11.5 m

Angle of projection, θ = 39.5°

Vertical components of veloclty = usinθ

Horizontal components of veloclty = ucosθ

The soft ball hits the water after time 't'

Considering the second equation of motion

S = ut + 1/2at^2........ 1

But since the ball went through motion under gravity ( free fall ) rather than linear motion, then equation 1 can be rewritten as:

H = ut +/- 1/2gt^2

H = - 11.5m

U = usinθ

θ = 39.5°

a = -g = -9.8m/s^2

- 11.5m = 23.5(sin39.5°)t + 1/2(-9.8)t^2

-11.5m = 23.5(0.6360)t - 4.9t^2

-11.5m = 14.946t - 4.9t^2

4.9t^2 -14.946t-11.5m = 0

Since the ball drifted horizontally

D = (Ucosθ)t

Where θ = 39.5°

U = 23.5m/s t=

Alternatively,

horizontal component of the velocity is 23.5 cos 39.5º = 18.1331 m/s

now how long does it take the ball to raise to a peak and fall to the water.

vertical component of velocity = 23.5 sin 39.5º = 14.947m/s

time to reach peak t = v/g = 11.947/9.8 = 1.5252 sec

peak reached above cliff top is

h = ½gt² = ½(9.8)(1.5252)²

= ½×22.797

= 11.3985m

now the ball has to fall 11.3985+ 11.5 = 22.8985m

time to fall from that height is

t = √(2h/g) = √(2• 22.8986/9.8) = 2.1617 sec

add up the two times to get time it is in the air, 2.1617 + 1.5252 = 3.6869

now haw far does the ball travel horizontally in that time

d = vt = 18.1331 ×3.6869= 66.856m

= 66.86m

Answer:

A gas usually has much lower density than a solid or liquid. ... The molecules or atoms in a gas are much further apart than in a solid or a liquid. Gas molecules or atoms are usually flying around at very high speeds, occasionally bouncing off each other or the walls of the container the gas is in.

Answer:

The volume of the cylinder is [tex]653.71\ \text{cm}^3[/tex]

Explanation:

Given that,

The height of the cylinder is 13 cm

Radius of the cylinder is 4 cm

We need to find the volume of the cylinder. The formula that is used to find the volume of a cylinder is given by :

[tex]V=\pi r^2 h\\\\V=\dfrac{22}{7} \times (4)^2 \times 13\\\\V=653.71\ \text{cm}^3[/tex]

So, the volume of the cylinder is [tex]653.71\ \text{cm}^3[/tex]

Answer:

653.45 is the answer

Explanation:

Answer:

C)-16 N

Explanation:

concepts used

force = mass* acceleration

equation of motion

[tex]v^2 = u^2 + 2as[/tex]

where v is the final velocity

u is the initial velocity

and s is the distance moved

______________________________________________

Given

mass = 1 kg

initial velocity (u) = 40m/s

final velocity (v) = 0 as stones comes to rest

distance moved by stone (s) = 50m

using  [tex]v^2 = u^2 + 2as[/tex]

[tex]0 = 40^2 +2a*50\\=> -1600 = 100a\\=> a = -1600/100 = -16[/tex]

Thus, acceleration is -16 m/s^2

here acceleration is negative as force of friction is opposing the motion.

Force of friction = mass of stone * acceleration of stone

Force of friction = 1*-16 kgm/s^2 = -16N       ( kgm/s^2 = 1 N)

Thus, option c -16N is correct choice.

Answer:

Hey there!

Mixtures are physically combined and can be separated. For example, sand and water is a mixture.

Pure substances are samples of matter with definite, and unchangeable chemical properties. For example, diamond is a pure substance.

Let me know if this helps :)

a pure substance is a substance that has not been mixed with anything, a mixture has been mixed with another substance. an example is

dirt +water=mud iron is an example of a substance

Answer:

option A

Explanation:

STOVE RADIATE ENERGY

Answer:

Distance : 0.06533 meters or 65.33 mm

Explanation:

To solve this problem we can make the forces equal when the system is at equilibrium.

mass [tex]*[/tex] gravity ( constant ) = spring constant

where l = the length at which the rubber band is stretched

0.2 kg [tex]*[/tex] 9.8 m / s² = 30 N/m

1.96 kg [tex]*[/tex] m / s² = 30 N/m

l = 1.96 kg [tex]*[/tex] m / s² / 30 N/m = 0.06533 meters / 65.33 mm

The rubber band is stretched a distance of 0.06533 meters, or 65.33 mm.

Answer:

0.065

Explanation:

Apex i just got it right

Answer:

1. direction of propagation of sound

2.medium through which sound trsnsmitted

Answer:

True

Explanation:

This is in fact what the Archimedes principle states, and what he used in the famous anecdote about finding if  the crown of the King was really made of gold.

Answer:  A Battery contains chemical energy which transfers electrical energy into the phone, powering it and also transferring Light energy, Sound energy and Heat energy.

Explanation:

Answer:

The nail exerts an equal force on the hammer in the opposite direction.

Explanation:

The Newtons third law states that there is an equal an opposite reaction for every action. When hammer pushes the nail, the nail will push the hammer back in opposite direction. When the hammer hits a nail then nail will exert the equal and opposite force to the hammer. These both objects will exert force on each other in opposite directions.

Hello, I am BrotherEye

Answer:

Answers are

1. "The nail exerts an equal force on the hammer in the opposite direction."

2. "500 N"

3. "The iron piece exerts a force of 1 N on the magnet in the opposite direction."

4. "When mass moves closer to the point of rotation, rotational inertia decreases."

5. "The skater spins slower because his rotational inertia has increased."

Explanation:

Answer:

The answer is B, true.

Because same current flows through each resistors in Series.

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[tex] \LARGE{ \underline{ \tt{ \pink{True \: or \: False}}}}[/tex]

The above statement is true.

❍ In series combination of resistors, the total electric current is equal to the current flowing through each resistor..

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