A train moves from rest to a speed of 25 m/s in 30.0 seconds. What is its acceleration?
Please provide the formula and the working

Answer:

Surface tension is a fundamental property of the surface of liquid. Surface tension is responsible for the curvature of the surfaces of air and liquids. Surface tension is responsible for the ability of some solid objects to “float” on the surface of a liquid.

hope it helps

Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible.Surface tension is what allows any object that is denser than water to float on water

hope this will help out

Answer:

Explanation:

Since we are looking at speed over a time unit, we have an acceleration graph. The definition of acceleration mathematically is:

[tex]a=\frac{v_f-v_0}{t}[/tex] (that's the change in velocity over the change in time). The slope of any line in this graph wil represent the acceleration. Slope is rise over run, or y over x. Therefore, if acceleration is velocity over time, then the y axis is the velocity axis and the x axis is the time axis. It makes perfect, beautiful sense!!

Answer:

Speed = 300 m/s

Explanation:

Given the following data;

Frequency = 30 Hz

Wavelength = 10 m

To find the speed of the wave;

Mathematically, the speed of a wave is given by the formula:

[tex] Speed = wavelength * frequency [/tex]

Substituting into the formula, we have;

[tex] Speed = 10 * 30 [/tex]

Speed = 300 m/s

Explanation:

everything can be found in the picture

Answer:

Original Length = L1

Stretched length =L2

From

R = pl/A

R=Resistance

p=Resistivity

A=Cross-sectional Area

l= length of wire

We can see that Resistance is directly Proportional to Length... Meaning that Resistance Increases also as Length increases.

R1/L1 = R2/L2

From the question... The key to note is this sentence

"The Stretched length is TWICE the Original Length"

Meaning

L2 = 2L1 (So replace L2 as 2L1 when solving)

R1=20ohms

Let R2 = k

Applying the formula

20/L1 = k/2L1

kL1 = 20x 2 L1

KL1 = 40L1

L1 cancels on both sides

k=40ohms.

So As the length doubled... The Resistance did too

from 20ohms to 40ohms

Answer:

It is a song called Come out and Play. It is released on 1994 in a Album called Smash. It comes under Punk-Rock.

I hope i answered your Question.

Answer:

Explanation:

Adding to the other answer, this song is about violence in streets and schools among young people involved in gangs; how they have little hope for their future. Band member Dexter got idea to make the song while he was in college.

Answer:

the person who invented gravity

Explanation:

newton was a mathmaticians when one day an apple fell on him. he had the idea to name the force gravity. While he "made" gravity he made other important laws the 3 newton laws of physics

Answer:

Issac Newton was around in the 1600s and early 1700s and is a very important mathematician and invented calculus.

Explanation:

Answer:

[tex]x=0.0498[/tex]

[tex]x'=0.659[/tex]

Explanation:

Specific Volume [tex]V=0.2m_3/kg[/tex]

Absolute Pressure (a) [tex]P_a= 40kpa[/tex]

Giving

[tex]T_a=75.87[/tex]

[tex]v_f=1.265*10^{-3}m^3/kg[/tex]

[tex]v_g=3.993m^3/kg[/tex]

                               (b) [tex]P_a= 630kpa[/tex]

Giving

[tex]T_b=160.13C[/tex]

[tex]v_f'=1.10282*10^{-3} m^3/kg[/tex]

[tex]v_g'=0.30286 m^3/kg[/tex]

(a)

Generally the equation for quality of Steam X  is mathematically given by

[tex]x=\frac{v-v_f}{v_g-v_f}[/tex]

[tex]x=\frac{0.2-1.0265*10^{-3}}{3.993-1.0265*10^{-3}}[/tex]

[tex]x=0.0498[/tex]

(b)

Generally the equation for quality of Steam X  is mathematically given by

[tex]x'=\frac{v-v_f'}{v_g'-v_f'}[/tex]

[tex]x'=\frac{0.2-1.10*10^{-3}}{3.30-1.1*10^{-3}}[/tex]

[tex]x'=0.659[/tex]

Answer:

CGS means Centimeter Gram Second while FPS means Foot Pounds Second

Explanation:

FPS is the standard used to measurement of length, mass and time. The unit of length is foot.

The time is calculated as the unit of seconds. CGS is the measurement of length, mass and time in units of centimeter, gram and second respectively

Answer:

B.

Hope this helps

Answer:

g = 0.4 m/s²

Explanation:

Given the following data;

Height = 5 meters

Time = 5 seconds

To find the acceleration due to gravity (g) on the planet;

Mathematically, the maximum height of an object is given by the formula;

H = ½gt²

Where;

H is the height measured in meters.

g is the acceleration due to gravity.

t is time measured in seconds.

Substituting into the formula, we have;

5 = ½ * g * 5²

5 = 0.5 * g * 25

5 = 12.5 * g

g = 5/12.5

g = 0.4 m/s²

The question is: The weight (w) of a person on Earth is 550N. Determine the mass (m) of the person and the weight (w) of the person on the Moon.

Answer: The mass (m) of the person is 550 N and the weight (w) of the person on the Moon is 891 kg.

Explanation:

Given: Mass = 550 N

When a person moves towards moon then its mass will remain the same but there will occur change in its weight because the acceleration due to gravity on moon is different than that on Earth.

Therefore, formula used to calculate the weight of person on moon is as follows.

[tex]W = m \times g_{m}[/tex]

where,

m = mass

[tex]g_{m}[/tex] = acceleration due to gravity on moon = 1.62 [tex]m/s^{2}[/tex]

Substitute the values into above formula as follows.

[tex]W = m \times g_{m}\\= 550 N \times 1.62 m/s^{2}\\ (1 N = 1 kg \times m/s^{2})\\= 891 kg[/tex]

Thus, we can conclude that the mass (m) of the person is 550 N and the weight (w) of the person on the Moon is 891 kg.

Answer:

Matter is a substance that has inertia and occupies physical space. According to modern physics, matter consists of various types of particles, each with mass and size.Matter can exist in several states, also called phases. The three most common states are known as solid, liquid and gas.Matter is the Stuff Around You or Atoms and compounds are all made of very small parts of matter. Those atoms go on to build the things you see and touch every day. Matter is defined as anything that has mass and takes up space (it has volume).Solid ice, water and steam are few examples of matter touched in everyday life. Subatomic particles are also considered as matter.

Answer:

Matter is everything around you. Atoms and compounds are all made of very small parts of matter. Those atoms go on to build the things you see and touch every day. Matter is defined as anything that has mass and takes up space (it has volume).

hope it helps...

Answer: 10 V, 40 V

Explanation:

Given

Resistors are [tex]500\Omega[/tex] and [tex]2000\Omega[/tex]

Power supply [tex]V=60\ V[/tex]

Voltmeter internal resistance [tex]r=2000\ \Omega[/tex]

When it connected around [tex]500\Omega[/tex] resistance, effective resistance becomes

[tex]\Rightarrow \dfrac{1}{R}=\dfrac{1}{500}+\dfrac{1}{2000}\\\\\Rightarrow R=\dfrac{2000}{5}\\\\\Rightarrow R=400\ \Omega[/tex]

Total resistance in series [tex]R_{net}=2400\ \Omega[/tex]

Current in circuit

[tex]I=\dfrac{60}{2400}=\dfrac{1}{40}\ A[/tex]

Voltage around [tex]500\Omega[/tex] resistance is

[tex]V=\dfrac{1}{40}\times 400\\\\V=10\ V[/tex]

(B) when voltmeter is connected around [tex]2000\Omega[/tex]  resistor

Net resistance around it

[tex]\Rightarrow \dfrac{1}{R}=\dfrac{1}{2000}+\dfrac{1}{2000}\\\\\Rightarrow R=1000\ \Omega[/tex]

Total resistance [tex]R_{net}=1500\ \Omega[/tex]

Current in circuit

[tex]I=\dfrac{60}{1500}=\dfrac{1}{25}\ A[/tex]

Voltage around [tex]2000\Omega[/tex] resistor

[tex]V=\dfrac{1}{25}\times 1000\\\\V=40\ V[/tex]

Answer:

OK HERE

Explanation:

When raising a power to a power in an exponential expression, you find the new power by multiplying the two powers together. For example, in the following expression, x to the power of 3 is being raised to the power of 6, and so you would multiply 3 and 6 to find the new power.

Answer:

D. A negative externality.

Explanation:

Particulate pollution is a form of pollution that is responsible for the degradation of the environment.

Particulate matter is also referred to as particle pollution or atmospheric aerosol particles and it can be defined as a complex microscopic mixture of liquid droplets and solid particles that are suspended in air.

An externality is typically an unwarranted cost or benefit by a manufacturer or producer of goods and services that affects a third party.

In Economics, an externality could either be positive or negative depending on its effect on a third party.

A negative externality arises when the production or consumption of a finished product or service has negative impact (cost) on a third party.

In conclusion, air pollution is an example of a negative externality because it causes harm to a third party.

Explanation:

the electric current is ratio of electric poer to the voltage

Answer:

(a) 8 V, (b) 144000 V, (c) 2 x 10^(-8) C

Explanation:

(a) charge, q = 5 μC , Work, W = 40 x 10-^(-6) J

The electric potential is given by

W = q V

[tex]40\times10^{-6}=5 \times10^{-6}\times V\\\\V = 8 V[/tex]

(b)

charge, q = 8 x 10^(-6) C, distance, r = 50 cm = 0.5 m

Let the potential is V.

[tex]V =\frac{k q}{r}\\\\V =\frac{9\times 10^{9}\times 8\times 10^{-6}}{0.5}\\\\V =144000 V[/tex]

(c)

Work, W = 8 x 10^(-5) J, Potential difference, V = 4000 V

Let the charge is q.

W= q V

[tex]8\times10^{-5}= q\times 4000\\\\q =2\times 10^{-8} C[/tex]

Answer:20Hz to 20000Hz

Explanation:

Humans can detect sounds in a frequency range from about 20 Hz to 20 kHz.

Answer:

p = 18 kg-m/s

Explanation:

Given that,

The mass of tyre, m = 6 kg

The velocity of the tyre, v = 3 m/s

We need to find the momentum of the tyre. We know that, the momentum of an object is equal to the product of mass and velocity. SO,

p = mv

[tex]p=6\ kg\times 3\ m/s\\\\=18\ kg-m/s[/tex]

So, the momentum of the tyre is equal to 18 kg-m/s.

Answer:

D. A nucleus of 2 protons and 2 neutrons.

Explanation:

A stable nucleus is one that do not disintegrate naturally, majorly due to the even number of its protons and neutrons. Thus they are not radioactive in nature.

From the given question, it would be observed that a nucleus of 2 protons and 2 neutrons would give a helium atom. And this is a stable atoms due to the magnetic number of the components of its nucleus.

Thus, the nuclear configuration that is most stable out of the given options is a nucleus of 2 protons and 2 neutrons. Option D.

Answer:

Efficiency = 0.575 = 57.5%

Explanation:

First, we will calculate the output energy of the elevator, which is equal to the potential energy acquired by the load.

[tex]O = Potential\ Energy\\O = mgh[/tex]

where,

O = Output = ?

mg = W = Weight = 12500 N

h = height = 29 m

Therefore,

[tex]O = (12500\ N)(29\ m) \\O = 362500\ J = 362.5\ KJ[/tex]

The input is given as:

I = 630 KJ

Thus the efficiency will be:

[tex]Efficiency = \frac{O}{I} = \frac{362.5\ KJ}{630\ KJ}\\\\[/tex]

Efficiency = 0.575 = 57.5%

Answer:

El peso = 245 Newton

Explanation:

Dados los siguientes datos;

Masa = 25 kg

Para encontrar el peso del perro en la tierra;

El peso se puede definir como la fuerza que actúa sobre un cuerpo o un objeto como resultado de la gravedad.

Matemáticamente, el peso de un objeto viene dado por la fórmula;

[tex] El \; peso = mg [/tex]

Dónde;

m es la masa del objeto.

g es la aceleración debida a la gravedad.

Sabemos que la aceleración debida a la gravedad es igual a 9,8 m / s² en el planeta Tierra.

Sustituyendo en la ecuación, tenemos;

[tex] W = 25 * 9.8[/tex]

El peso = 245 Newton

Answer:

La entropía del vapor de mercurio cambia en 214.235 joules por Kelvin.

Explanation:

Por definición de entropía ([tex]S[/tex]), medida en joules por Kelvin, tenemos la siguiente expresión:

[tex]dS = \frac{\delta Q}{T}[/tex] (1)

Donde:

[tex]Q[/tex] - Ganancia de calor, en joules.

[tex]T[/tex] - Temperatura del sistema, en Kelvin.

Ampliamos (1) por la definición de calor latente:

[tex]dS = \frac{L_{v}}{T}\cdot dm[/tex] (1b)

Donde:

[tex]m[/tex] - Masa del sistema, en kilogramos.

[tex]L_{v}[/tex] - Calor latente de vaporización, en joules

Puesto que no existe cambio en la temperatura durante el proceso de vaporización, transformamos la expresión diferencial en expresión de diferencia, es decir:

[tex]\Delta S = \frac{\Delta m \cdot L_{v}}{T}[/tex]

Como vemos, el cambio de la entropía asociada al cambio de fase del mercurio es directamente proporcional a la masa del sistema. Si tenemos que [tex]m = 0.50\,kg[/tex],[tex]L_{v} = 2.7\times 10^{5}\,\frac{J}{kg}[/tex] and [tex]T = 630.15\,K[/tex], entonces el cambio de entropía es:

[tex]\Delta S = \frac{(0.50\,kg)\cdot \left(2.7\times 10^{5}\,\frac{J}{kg} \right)}{630.15\,K}[/tex]

[tex]\Delta S = 214.235 \,\frac{J}{K}[/tex]

La entropía del vapor de mercurio cambia en 214.235 joules por Kelvin.

Answer:

Parallel combination

Explanation:

When the two resistances are connected in parallel then the equivalent resistance is

[tex]\frac{1}{R}=\frac{1}{R'}+\frac{1}{R''}[/tex]

To get the minimum resistance of a circuit, the circuit components should be connected in parallel combination.

In the parallel combination, the voltage across each resistor is same and the current is divided in every resistance according to the resistances.

Answer:

The initial velocity of the pooper off the table is approximately 9.264 m/s

Explanation:

The mass of the popper, m = 0.1 kg

The height the popper reaches, h = 2.0 meters

The initial velocity of the popper, 'u', is given by the following kinematic relation;

v² = u² - 2·g·h

Where;

h = The height the popper reaches = 2.0 m

v = The final velocity of the popper at the height it reached = 0 m/s

u = The initial velocity of the pooper off the table

g = The acceleration du to gravity, g ≈ 9.81 m/s²

Plugging in the values gives;

0² = u² - 2 × 9.81 × 2.0

∴ u - √(2 × 9.81 × 2.0) ≈ 9.264

The initial velocity of the pooper off the table, u ≈ 9.264 m/s.