a teacher and two students are mesuring the speed of sound. the teacher makes loud sound by hitting two cymbals together. each students starts a stopwatch then they see the teacher hit the cymbals, they each stop their stop watch when they hear the sound. describe how a sound wave moves through the air.​

Answer:

c) sin c /sin d

because light is moving from denser to shallower medium

b) refraction of light

Explanation:

Answer:

each resistor draws 1/3 of an amp or 0.33333 amps

Explanation:

V = I * R

V = 10 volts

R = 30 ohms

10 = I * 30       Divide by 30

10/30 = I

I = 0.33333

Answer:

Option A.

Explanation:

We define the half time T as the time such that an initial quantity A reduces to its half.

So we can model the quantity as a function of time like:

P(t) = A*e^(-k*t)

Then for the half time, T, we will have:

P(T) = A/2 = A*e^(-k*T)

solving for k, we get:

A/2 = A*e^(-k*T)

1/2 = e^(-k*T)

ln(1/2) = ln( e^(-k*T)) = -k*T

-ln(1/2)/T = k

Here we know that the half time is T = 26.5s

if we input that in the above equation, we get:

-ln(1/2)/26.5s = k = 0.0262 s^-1

Then the correct option is A

Answer:

Distancia, D = 170,000 metros

Explanation:

Dados los siguientes datos;

Para encontrar la distancia recorrida, en metros;

Matemáticamente, la distancia recorrida por un objeto se calcula mediante la fórmula;

Distancia = velocidad * tiempo

Sustituyendo los valores en la fórmula, tenemos;

Distancia = 85 * 2

Distancia = 170 kilómetros

A continuación, convertiríamos el valor en kilómetros a metros;

Conversión:

1 kilómetros = 1000 metros

170 kilómetros = D metros

Multiplicación cruzada, tenemos;

D = 170 * 1000

D = 170,000 metros

Por lo tanto, habría viajado 170,000 metros después de 2 horas.

Answer:

Rotational kinetic energy

Explanation:

It is caused by circular motion.

Answer:

electric current=ampere(A)

force=Newton (N)

area=metres square(m^2)

power=watt(w)

density=kg/m3 

amount of substance =mole per cubic meter (mol/m3).

volume=cubic meter (m3),

Answer:

thanks for brainlist brother.........

Answer:

The momentum makes it worse.

Explanation:

The momentum of vehicles running at faster speeds is very high and causes a lot of damage to the vehicles.

Gamma rays

used in radiotherapy

Answer:

Explanation:

The gravitational force between the earth and another body is F = -GM_em/r^2 r where G = 6.67 times 10^-11 Nm^2/kg^2 is the gravitational constant, M_e = 5.97 times 10^24 kg is the mass of the earth, m is the mass of the other body, and r is the position vector of the second body with respect to the centre of the earth.

Answer:

25 mm = 0 deg C

200 mm = 100 deg C

200 - 25 = 175 = change in thread per 100 deg C

95 - 25 = 70 mm - change in thread from 0 deg C

70 / 175 * 100 = 40 deg C    final temperature at 95 mm

The dimension of a/b where x is the distance and t is the time is T

Given the expression

x = at + bt²

where

x is the distance

t is the time

Based on the homogeneity principle, the expression on the left-hand side must be equal to that on the right. Hence;

x = at

[tex]a = \frac{x}{t}[/tex]

Since x is the distance and distance is measured in metres, the dimension equivalent will be the length 'L'

Since t is the time and time is measured in seconds, the dimension equivalent will be the seconds 'T'

[tex]a=\frac{L}{T}[/tex]

Similarly;

x  = bt²

[tex]b=\frac{x}{t^2}\\b=\frac{L}{T^2}[/tex]

Next is to get a/b;

[tex]\frac{a}{b} = \frac{L}{T} \div \frac{L}{T^2}\\\frac{a}{b} = \frac{L}{T}*\frac{T^2}{L} \\\frac{a}{b} =\frac{T^2}{T}\\\frac{a}{b} =T[/tex]

Hence the dimension of a/b is T

(a) The de Broglie wavelength is approximately 5.175 × 10⁻¹⁵  meters. The wavelength is lesser than the distance of closest approach

(b) It is proper to treat the alpha particle as a particle and not as wave because the distance of closest approach is much larger than and not comparable to its wavelength for the alpha particle for the alpha particle to be treated as a wave

The given parameters are;

The kinetic energy of the alpha particles = 7.70 MeV = 1.23368 × 10⁻¹² J

The distance from the gold nucleus the alpha particles reach = 29.5 fm

(a) The de Broglie wavelength of a particle is given as follows;

[tex]\mathbf{\lambda = \dfrac{h}{p}}[/tex]

Where;

λ = The wavelength

h = Planck's constant = 6.62607004 × 10⁻³⁴ m²·kg/s

p = The momentum of the particle = Mass of an electron, m × Velocity, v

The mass of an alpha particle, m ≈ 6.645 × 10⁻²⁷ kg

Therefore;

[tex]\lambda = \dfrac{h}{m \times v}[/tex]

The kinetic energy of the alpha particle, K.E. = (1/2)·m·v²

∴ v = √(2 × K.E./m)

Therefore;

[tex]\lambda = \dfrac{h}{m \times \sqrt{2 \times \dfrac{K.E.}{m} } } = \dfrac{h}{ \sqrt{2 \times m \times K.E.} }[/tex]

Plugging in the values of the variables gives;

[tex]\lambda = \dfrac{6.62607004 \times 10 ^{-34} }{ \sqrt{2 \times 6.645 \times 10 ^{-27} \times 1.23368 \times 10^{-12} } } \approx 5.175 \times 10^{-15}[/tex]

The de Broglie wavelength of the alpha particle, λ ≈ 5.175 × 10⁻¹⁵ m

The distance of closest approach = 29.5 fm = 29.5 × 10⁻¹⁵ m

Compared to the distance of closest approach, the wavelength of the alpha particle is lesser than the distance of closest approach

(b)  Given that the distance of closest approach is six times larger than the wavelength of the alpha particle, and alpha particle behaving as waves are expected to approach closer to the gold nucleus in the region of their wavelength before deflection, therefore, the larger distance of closest approach is indicative of a charged particle to charged particle interaction, and therefore, particle behavior of alpha particles.

Learn more about de Broglie wavelength, particles and wave behavior of radiation here;

https://brainly.com/question/22471405

https://brainly.com/question/17403491

https://brainly.com/question/15128575

Explanation:

The derivative of a constant term is always 0. So the acceleration of the body would be zero. Hence, the acceleration of a body moving with uniform velocity will always be zero.

hope it helps you

Answer:

D. crystalline solid that conducts current under certain conditions

Explanation:

Semiconductors are crystalline solids that has the ability to conduct electrical currents but on certain conditions e.g heat. The conduction of semiconductors is less than that of conductors (metals) but more than insulators (nonmetals), hence, they are said to be intermediates of conductors and insulators in terms of electrical conductivity.

Examples of semiconductors are silicon, boron, carbon, germanium, arsenic etc.

Answer: The answer is B

Explanation:

There are 4 fundamental forces that hold matter together.

- Gravitational Force

- Electromagnetic Force

- Strong Nuclear Force

- Weak Nuclear Force

We have barely just scratched the info about nuclear forces but the reason why B is the answer to the question is that Strong nuclear force actually holds the protons and neutrons together in the nucleus of an atom, much like the picture in B.

Answer: B

Explanation:

Answer:

the specific heat capa city of the aluminium is 900 joules per kilogram per °C.

Am I right please?

Answer:

electric current is derived unit.

Explanation:

According to the definition of electric current, it appears to be a derived quantity. Charge on the other hand seems more fundamental than electric current.

Answer:

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Answer:

B. Km/s/hr

Explanation:

Answer:

120 Nm-1

Explanation:

Según la ley de Hooke;

F = Ke

F = fuerza sobre el resorte

K = constante de fuerza

e = extensión

Por eso;

K = F / e

K = 24N / 20 × 10 ^ -2m

K = 120 Nm-1

Answer:

Obeying to weights & measurement regulations in both national and international metrology legislation, standards and test procedures is a requirement to participate in any market because it's aimed to safeguard the consumers and promote fair competition, which provides efficiency and saves unnecessary costs to U.S. businesses and stakeholders.

Explanation:

In the U.S., the National Institute of Standards and Technology (NIST) has an Office of Weights and Measures (OWM) that represents the country in the International Organization of Legal Metrology (OIML)

Answer:

6 Ways To Promote Peace

Treat all people with kindness, regardless of race, gender orientation, sexual orientation, religion, etc.

Attend a peace rally.

Write to your government (local and federal)

Create a peaceful affirmation/mantra.

Don't engage in violence of any kind.

Don't purchase weapons.

Answer:

The elements are grouped into the different substances by color. As you can see, Lithium, Beryllium, Sodium, Magnesium, Aluminum, Potassium, and Calcium are metals out of the first 20 elements.

Hydrogen, Helium, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Phosphorus, Sulfur, Chlorine, and Argon, are non-metals within the first 20 elements.

Boron and Silicon count as Metalloids in the Periodic Table (properties of both metals and non-metals)

reference- socatric q and a

Explanation:

Answer:

(11-13) - Metals

(14) - Metalloid

(15-18) - Non- metals

(19-20) - Metals

Explanation:

The elements from 11 to 13 are metals. They are Sodium(Na), Magnesium(Mg) and Aluminum(Al) respectively.

The element 14 is a metalloid. It’s Silicon(Si).

The elements from 15 to 18 are non metals. The 18th element is a noble gas known as Argon(Ar).

The elements from 15 to 17 are Phosphorus(P), Sulphur(S) and Chlorine(Cl).

The elements from 19 to 20 are metals. They are Potassium(K) and Calcium(Ca).

Answer:

Velocity is the rate of change of position with respect to time, whereas acceleration is the rate of change of velocity. Both are vector quantities (and so also have a specified direction), but the units of velocity are meters per second while the units of acceleration are meters per second squared.

Answer:

The separation between the two stones is 36 m, when the second stone is approximately 10.9 m below the top of the cliff

Explanation:

The given parameters are;

The height of the cliff from which the stones are dropped, h = 60 m

The time at which the second stone is dropped = 1.6 seconds after the first

The distance below the top of the cliff when the distance between the two stones is 36 m = Required

We have;

The kinematic equation of motion that can be used is s = u·t - (1/2)·g·t²

For the first stone, we have, s₁ = u·t₁ - (1/2)·g·t₁²

For the second stone, we get; s₂ = u·t₂ - (1/2)·g·t₂²

t₁ = t₂ + 1.6

g = The acceleration due to gravity ≈ 9.81 m/s²

s = The distance below the cliff top

The initial velocity of the stones, u = 0

Let t represent the time from which the second stone is dropped at which the distance between the two stones is 36 m, we have;

s₁ = u·(t + 1.6) + (1/2)·g·(t + 1.6)²

s₂ = u·t + (1/2)·g·t²

u = 0

∴ s₁ - s₂ = 36 =  (1/2)·g·(t + 1.6)² - (1/2)·g·t²

2 × 36/(g) = (t + 1.6)² - t²  = t² + 3.2·t + 2.56 - t² = 3.2·t + 2.56

2 × 36/(9.81) = 3.2·t + 2.56

t = (2 × 36/(9.81) - 2.56)/3.2 =  ≈ 1.49 s

t ≈ 1.49 s

s₂ = (1/2)·g·t²

∴ s₂ = (1/2) × 9.81 × 1.49² ≈ 10.9

The distance below the top of the cliff of the second stone when the the separation between the two stones is 36 m, s₂ ≈ 10.9 m.

I think it is a education tips

Explanation:

If the mass of the inclined plane is large enough, could N ever be equal to mgcosθ. Reasons?

So far I've come up with: mgcosθ−N=ma meaning if N were to equal mgcosθ, ma=0. Since the surfaces are frictionless and since N is acting on the inclined plane too(it'll have a horizontal component), this isn't possible. Am I right? Where am I going wrong?

Answer:

A. Contains DNA

C. Contains ribosomes

F. Lacks a nucleus

Explanation:

Answer:

Explanation:

The first part of this question is simply asking us to convert the speed from miles per hour to meters per second:

[tex]60.0\frac{mi}{hr}*\frac{1hr}{3600sec}*\frac{1609.34m}{1mi}=26.8\frac{m}{s}[/tex] choice C.

The next part wants us to use the equation for acceleration and find the acceleration:

[tex]a=\frac{v-v_0}{t}[/tex] where v is final velocity, v0 is initial velocity, and t is time in seconds (which was one of the reasons we had to convert the initial velocity from 60.0 mph to m/s):

[tex]a=\frac{26.8-0}{2.5}[/tex] and

a = 10.7 m/s/s, choice B.