chuyển động thẳng đều là gì

Answers

Answer 1

Question:

What is uniform rectilinear motion?

Answer:

Uniform rectilinear motion is when an object travels at a constant speed with zero acceleration.


Related Questions

Un globo contiene 4 moles de un gas ideal con un volúmen de 5,0 L. Si se agregan 8 moles adicionales del gas a presión y temperatura constantes, ¿Cuál será el volumen final del globo? - ¿Cuál es la densidad (en g / L) de un gas con una masa molar de 60 g / mol a 0,75 atm y 27 ° C?

Answers

Tenemos un problema de termodinamica sobre gases ideales, los cuales pueden ser descritos por la ecuación de estado del gas ideal

[tex]P*V = n*R*T[/tex]

donde:

P = presión

V = volumen

n = número de moles

R = constante de los gases

T = temperatura.

1) Para el primer problema podemos pensar que el gas dentro del globo es un gas ideal:

Originalmente sabemos que n = 4 y V = 5.0 L

Entonces tendremos:

[tex]P*(5.0 L) = (4 moles)*R*T[/tex]

Ahora decidimos agregar 8 moles más, dejando constante la presión y la temperatura, entonces podemos reescribir la ecuación de arriba como:

(5.0L)/(4 moles) = R*T/P

Y como R, T y P son constantes, entonces:

R*T/P es una constante.

Esto quiere decir que cuando agreguemos 8 moles, para tener un total de 12 moles, tendremos que:

V'/(12 moles) = R*T/P = (5.0L)/(4 moles)

Donde V' es el nuevo volumen final del globo, y es lo que queremos obtener.

V'/(12 moles) =  (5.0L)/(4 moles)

V' =   (5.0L)*(12 moles)/(4 moles) = (5.0 L)*3 = 15.0 L

2) Queremos obtener la densidad en gramos sobre litro de un gas con una masa molar de 60g/mol, a P = 0.75 atm y T = 25°C.

Primero pasemos la temperatura a grados kelvin:

T = 25°C = (25 + 273.15)°K = 298.15°K

Planteamos la ecuación del gas ideal:

[tex]P*V = n*R*T[/tex]

reemplazando R = 0.082 (atm*L/mol*k), además de la presión y la temperatura para un solo mol de gas:

[tex](0.75 atm)*V = (1 mol)*(0.082 (atm*L/mol*k))*(298.15°K)[/tex]

Resolviendo para V obtenemos que:

 

[tex]V = (1 mol)*(0.082 (atm*L/mol*k))*(298.15°K)/(0.75 atm) = 32.597 L[/tex]

Así, vemos que un mol de este gas ocupa un volumen de  32.597 L

Y también sabemos que un mol de este gas pesa 60 gramos.

Recordando que la densidad es el cociente entre la masa y el volumen, podemos ver que la densidad del gas será:

[tex]d = 60g/(32.597 L) = 1.84 g/L[/tex]

Si deseas leer mas sobre el tema, podes ver:

https://brainly.com/question/18528542

at what angle should the circular road be banked so that a car running at 50 km per hour be safe to go round the circular from of 200m radius​

Answers

Answer:

Mark brainliest please

answer is 5.5 degrees

Explanation:

Given,

Speed of car (v) = 50km/hr = 50×1000/60×60 m/s

Radius of circle (r) = 200m

Banking angle (θ) =?

we know ,

tanθ = v^2/rg

or , tanθ = (50×1000/60×60)^2/200×10 = 0.0965

∴ θ = tan-1(0.0965) = 5.5°

The number of windings on the primary coil of a transformer
is 1.5 times greater than on the secondary coil. The primary
coil has a current of 3.0 A and a voltage of 12.0 V. Determine
the voltage and current on the secondary coil.

Answers

Answer:

I. Vs = 8.0 Volts.

II. Is = 4.5 Amperes.

Explanation:

Given the following data;

Np = 1.5Ns = [tex] \frac {N_{P}}{N_{S}} = 1.5 [/tex]  ..... equation 1

Ip = 3.0 A

Vp = 12 V

To find the voltage and current on the secondary coil;

I. For the voltage in the secondary coil (Vs), we would use the following formula;

[tex] \frac {V_{P}}{V_{S}} = \frac {N_{P}}{N_{S}} [/tex]  ...... equation 2.

Substituting eqn 1 into eqn 2, we have;

[tex] \frac {V_{P}}{V_{S}} = 1.5 [/tex]

[tex] \frac {12}{V_{S}} = 1.5 [/tex]

Cross-multiplying, we have;

[tex] V_{S} * 1.5 = 12 [/tex]

[tex] V_{S} = \frac {12}{1.5} [/tex]

Vs = 8.0 V

II. For the current in the secondary coil (Is), we would use the following formula;

[tex] \frac {I_{S}}{I_{P}} = \frac {N_{P}}{N_{S}} [/tex]  .... equation 3

Substituting eqn 1 into eqn 3, we have;

[tex] \frac {I_{S}}{I_{P}} = 1.5 [/tex]

[tex] \frac {I_{S}}{3.0} = 1.5 [/tex]

Cross-multiplying, we have;

[tex] I_{S} = 1.5 * 3.0 [/tex]

Is = 4.5 A

A car travels first 10 km in 20 minutes and another 10 km in 30 minutes. What is the average speed of the car in m/s?

Answers

Total distance = 10 km + 10 km = 20 km

1 km = 1000 m

20km x 1000 = 20,000 m

Total time = 20 min. + 30 min. = 50 minutes

Average speed = Distance /  time

Average speed = 20,000/50 min

Average speed = 400 m/s

Use the KMT to explain what happens to water vapor when it encounters a
cold glass of water.

Answers

Answer:

The postulates of the Kinetic Molecular Theory, KMT, are;

(1) In an ideal gas the molecules are in constant motion

(2) The collisions between molecules of gases are perfectly elastic

(3) The volume occupied by the molecules are negligible

(4) The temperature of the gas is directly proportional to its kinetic energy

(5) The intermolecular forces in the gas are negligible

According to the KMT, gaseous water vapor molecules are in constant motion and move at a speed that depends on their temperature. The intermolecular forces between the molecules are negligible and when they collide with the cold glass, they lose temperature to the glass, thereby reducing their temperature, kinetic energy and therefore, their speed is reduced.

The increasingly temperature of the water vapor coming in contact with the cold glass gives rise to reduced speed of the cooled gas molecules, thereby causing them to move closer together after having elastic collisions and to cluster with tiny particles in the air, to form tiny droplets

The rapid cooling on the cold glass surface causes the droplets to form rapidly on the cold glass surface which makes them visible as condensed water on the surface of the cold glass of water

Explanation:

which physical property of the gas molecules gives the measurement of temperature​

Answers

The temperature of a gas molecule is measured by the average translational kinetic energy

Answer:

The temperature of a gas is a measure of the average translational kinetic energy of the molecules. In a hot gas, the molecules move faster than in a cold gas; the mass remains the same, but the kinetic energy, and hence the temperature, is greater because of the increased velocity of the molecules

Explanation:

This is also from Go0gle because my explanation would've been an essay long .

but in shorter version if the gas molecules move fast it's hot an if it moves slow its cold hope this helps .

what can be done to increase speed of rotation of a DC motor​

Answers

Answer: There are multiple options:

By varying the supply voltage.

By varying the flux, and by varying the current through the field winding.

By varying the armature voltage, and by varying the armature resistance.

Helpful Link:

https://www.elprocus.com/what-are-the-best-ways-to-control-the-speed-of-dc-motor/

hai điện tích q1 =-2.10^(-8), q2=1,8.10^(-8) đặt tại A và B trong không khí,AB=8cm. Một điện tích q3 đặt tại C. 1, C ở đâu để q3 cân bằng

Answers

Answer:

Đáp án là vị trí để đặt q3 tại vị trí cân bằng là cách A một đoạn 0,0411 m

và nằm trong AB

Explanation:

Do q1 và q2 trái dấu nên q3 nằm trong

gọi r1 là vị trí từ A đến q3 suy ra r2=0.08-r1

Vị trí cân bằng nên [tex]\frac{q1}{r1^{2} }[/tex] = [tex]\frac{q2}{(0.08-r1)^{2} }[/tex]

Si la fuerza de fricción cinetica es 250N ¿Qué fuerza se necesita para mantener a la caja deslizándose a una velocidad constante ¿

Answers

Answer:

250N

Explanation:

According to newton second law,

\sumF = ma

Fm - Ff = ma

Since the velocity is constant, a = 0m/s

Frictional force Ff = 250N

Substitute

Fm - 250 = m(0)

Fm - 250 = 0

Fm = 250N

Hence the force to keep the box sliding at constant speed is 250N

Una carga q1 = - 45 µC esta colocada a 30 mm a la izquierda de una carga q2 = 25 µC . ¿Cuál es la fuerza resultante sobre una carga de q3 = 20 µC localizada exactamente 50 mm arriba de la carga de 25µC ?

Answers

Answer:

La fuerza resultante sobre q₃ es  -1.2245 × 10⁻¹⁵ i  + -0.24 × 10⁻¹⁵ j

La magnitud de la fuerza resultante sobre q₃ es aproximadamente 1.25 × 10⁻¹⁵ N

Explanation:

q₁ = -45 μC = -45 × 10⁻⁶ C

r₁₂ = 30 mm = 30 × 10⁻³ m

q₂ = 25 μC = 25 × 10⁻⁶ C

r₂₃ = 50 mm = 50 × 10⁻³ m

q₃ = 20 μC = 20 × 10⁻⁶ C

k = 9×10⁻⁹ N·m²/C²

Por lo tanto;

r₁₃ = √(50² + 30²) = 10·√(34)

F₁₂ = 9×10⁻⁹ × (-45 × 10⁻⁶)×(25 × 10⁻⁶)/(30 × 10⁻³)² = -1.125 × 10⁻¹⁴

F₁₂ = -1.125 × 10⁻¹⁴ N

F₂₃ = 9×10⁻⁹ × (20 × 10⁻⁶)×(25 × 10⁻⁶)/(50 × 10⁻³)² = 1.8 × 10⁻¹⁵ j

F₁₃ = 9×10⁻⁹ × (-45 × 10⁻⁶)×(20 × 10⁻⁶)/(10·√34 × 10⁻³)² = -2.38× 10⁻¹⁵

Los componentes de F₁₃ son;

-2,38 × 10⁻¹⁵ × cos (arctan (30/50)) = -2,04 × 10⁻¹⁵ j

-2,38 × 10⁻¹⁵ × sin (arctan (30/50)) = -1,2245 × 10⁻¹⁵ i

La fuerza resultante sobre la carga q₃, [tex]\left | \underset {F_3} \rightarrow \right |[/tex] = [tex]\underset{F_{13}}{\rightarrow}[/tex] + [tex]\underset{F_{23}}{\rightarrow}[/tex]

∴ [tex]\left | \underset {F_3} \rightarrow \right |[/tex] = 1.8 × 10⁻¹⁵ j + -1.2245 × 10⁻¹⁵ i + -2.04 × 10⁻¹⁵ j

La fuerza resultante sobre q₃ es [tex]\left | \underset {F_3} \rightarrow \right |[/tex]  = -1.2245 × 10⁻¹⁵ i  + -0.24 × 10⁻¹⁵ j

La magnitud de la fuerza resultante sobre q₃,

[tex]\left | F_3 \right |[/tex] = √((-1.2245 × 10⁻¹⁵)² + (-0.24 × 10⁻¹⁵)²) ≈ 1.25 × 10⁻¹⁵

La magnitud de la fuerza resultante sobre q₃, [tex]\left | F_3 \right |[/tex] ≈ 1.25 × 10⁻¹⁵ N.

I shared a picture of the problem. It’s a basic Physics question and an Algebra question.

Answers

Hence the expression of ω in terms of m and k is

[tex]\omega = \sqrt{\frac{k}{m}[/tex]

Given the expressions;

[tex]T_s = 2 \pi \sqrt{\frac{m}{k} } \ and \ T_s = \frac{2 \pi}{\omega}[/tex]

Equating both expressions we will have;

[tex]2 \pi \sqrt{\frac{m}{k} } = \frac{2 \pi}{\omega}[/tex]

Divide both equations by 2π

[tex]\frac{2 \pi\sqrt{\frac{m}{2 \pi} } }{2 \pi}=\frac{\frac{2 \pi}{\omega} }{2\pi}\\\sqrt{\frac{m}{2 \pi} } = \frac{1}{\omega}\\[/tex]

Square both sides

[tex](\sqrt{\frac{m}{k} } )^2 = (\frac{1}{\omega} )^2\\\frac{m}{k} = \frac{1}{\omega ^2} \\\omega ^2 = \frac{k}{m}[/tex]

Take the square root of both sides

[tex]\sqrt{\omega ^2} =\sqrt{\frac{k}{m} } \\\omega = \sqrt{\frac{k}{m}[/tex]

Hence the expression of ω in terms of m and k is

[tex]\omega = \sqrt{\frac{k}{m}[/tex]

Learn more about subject of the formula here: https://brainly.com/question/19557491

The needle in the following diagram rotates around a fixed point in the middle. Based on the information given, what way will the needle rotate when the current is applied?

Answers

Answer:

nods 40th anniversary rid off e 49en9 snns

a motorcycle covers 500 meters in 25 seconds. calculate the average velocity​

Answers

Vtb xe máy là:

v=s : t= 500 : 25=20(m/s)

Imagine that you are using a similar computer simulation to conduct an experiment on ph value of different liquid hand soap solutions and water. What is a potential source for error in such a computer model?


Please help!!

Answers

The computer model would rely on the labeled pH values of various hand soap brands however the labled pH value might not be entirely accurate, which could comprise the accuracy of the computer model.

Inaccuracies in the simulation's underlying chemistry model could be a potential source of mistake in an experiment involving the pH values of several liquid hand soap solutions and water.

The outcomes could differ from actual behavior if the model does not adequately represent the intricate chemical interactions that control pH fluctuations. Furthermore, because they might not exactly match the varied properties of real hand soap solutions, the simulation's assumptions and parameters could introduce bias. Disparities between simulation results and empirical findings may also result from inadequate consideration of temperature impacts and ambient factors. To reduce such possible mistakes, careful simulation validation against empirical data and chemistry model modification are required.

To know more about empirical data, here

brainly.com/question/32634558

#SPJ3

A liquid has a density of 2 g/mL, the volume is measured at 20 ml,

Answers

Answer:

This isn't a question... Next time please ask a question.

Explanation:

why is the fuse used in a circuit called safety fuse?

Answers

Answer:

The maximum current which can flow through a fuse without melting it, is called its rating. ... If current higher than 8 A flows through the fuse, it would melt and circuit gets broken. ... Hence, fuse acts as a safety device

Answer:

The guy above me is right

Explanation:

What is Plancks Constant? Need it ASAP

Answers

Answer:

The Planck constant, or Planck's constant, is a fundamental physical constant denoted h, and is of fundamental importance in quantum mechanics. A photon's energy is equal to its frequency multiplied by the Planck constant. Due to mass–energy equivalence, the Planck constant also relates mass to frequency.

Theory:

Planck postulated that the energy of light is proportional to the frequency, and the constant that relates them is known as Planck's constant (h). His work led to Albert Einstein determining that light exists in discrete quanta of energy, or photons.

E = hf

[tex] \sf \: h = 6.626 \times {10}^{ - 34} \: kg \: {m}^{2} {s}^{ - 1} [/tex]

Microwaves operate at a frequency of 2.40 GHz. Find the minimum thickness for a plastic tray with a refractive
index of 1.45 that will cause enhanced reflection of microwaves incident normal to the tray.

Answers

Answer:

y (lambda) = c / f     incident wavelength

y = 3 * E8 / 2.4 * E9 = .125 m    incident wavelength

y' = .125 / 1.45 = .0862 m    wavelength inside of tray

T = y' / 4     thickness required for phase change at bottom

T = .0862 m / 4 = .0261 m = 2.61 cm

why can't we measure temperature or build thermometer if there is no zeroth law? thanks

Answers

Explanation:

The Zeroth Law of Thermodynamics states that if two bodies are each in ... to heat, there will be no transfer of heat from one to the other.

A tightrope walker is walking between two buildings holding a pole with length L=14.0 m, and mass mp=17.5 kg. The daredevil grips the pole with each hand a distance d=0.595 m from the center of the pole. A bird of mass mb=560 g lands on the very end of the left‑hand side of the pole. Assuming the daredevil applies upward forces with the left and right hands in a direction perpendicular to the pole, what magnitude of force Fleft and Fright must the left and right hand exert to counteract the torque of the bird?

Answers

Answer:

F = 32.28 N

Explanation:

For this exercise we must use the rotational equilibrium relation

          Σ τ = 0

In the initial configuration it is in equilibrium, for which all the torque and forces are compensated. By the time the payment lands on the bar, we assume that the counter-clockwise turns are positive.

          W_bird  L / 2 - F_left 0.595 - F_right 0.595 = 0

we assume that the magnitude of the forces applied by the hands is the same

          F_left = F_right = F

          W_bird L / 2 - 2 F 0.595 = 0

          F = [tex]\frac{m_{bird} \ g L} { 4 \ 0.595}[/tex]

   

we calculate

         F = 0.560 9.8 14.0 /2.38

         F = 32.28 N

what is the story of coal​

Answers

Explanation:

Coal is a fossil fuel and is the altered remains of prehistoric vegetation. The energy we get from coal today comes from the energy that plants absorbed from the sun millions of years ago. In the burning process of coal, carbon dioxide (CO2) is emitted. Humans expel CO2, and plants utilize it every single day. Carbon is a building block for all forms of life and is used in a lot of everyday products.

Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times. However, many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras.

Answer:

look it up of goog le

Explanation:

Does the scalar addition obey ordinary addition rules?

Answers

Explanation:

In scalar addition we have to do only the sum of magnitude as we know that the scalar quantities don't have direction.

since it is the scalar quantity the direction will be same for all the magnitudes.

Answer:

In scalar addition we have to do only the sum of magnitude as we know that the scalar quantities don't have direction...

since it is the scalar quantity the direction will be same for all the magnitudes.

on the other hand if it was a vector addition then it should be with two different directions which are considerable show the resultant vector needs to be calculated by vector addition method.

a car of mass 500 kg travelling with a speed of 54km/hr is brought to rest over a distance of 40 m. find the acceleration and force applied on brakes​

Answers

Answer:

Explanation:

[tex]a=\frac{v_f-v_0}{t}[/tex] We don't yet need the mass of the car, as we can see by this equation. What we do need is the velocity of the car, the initial velocity, in meters per second, and right now it's in km/hr. Not good. We need to convert. The conversion is as follows:

[tex]54\frac{km}{hr}*\frac{1000m}{1km}*\frac{1hr}{3600s}=15\frac{m}{s}[/tex] Ok, that's good. Now we have everything we need but the time element. If the car traveled a distance of 40 meters at 15 m/s, then we can use the d = rt equation to solve for t, and when we find t we plug it into the acceleration equation:

40 = 15t and

t = 2.7 seconds. The car traveled for 2.7 seconds to go that 40 meters. That's the only reason we were given the displacement. We need it for nothing else but that.

Filling in the acceleration equation now:

[tex]a=\frac{0-15}{2.7}=-5.6\frac{m}{s^2}[/tex] and the negative indicates we are in fact slowing down. That's the answer for the acceleration portion of the problem; now we need the force, F, applied to the brakes.

F = ma where m is mass (we get to use that value now!) and a is -5.6 m/s/s.

F = 500(-5.6) and

F = -2800 N and the negative here means that the force of the brakes is acting against the motion of the car: the brakes are pulling the car "backwards" to stop while the car's motion is forward. The negative indicates the direction the force is being applied.

The law of conservation of energy states that energy cannot be created or
destroyed, only converted into other forms.
True or false

Answers

Answer:

True

Explanation:

Yes, According to law of conservation of energy, it has been said that energy cannot be created or destroyed.

Which one of the following explains how light energy helps us see all kinds of objects around us?

a flashlight shining light on a book

Light is absorbed by the objects and does not reach our eyes.
The objects emit light that enters our eyes.
Light reflects off the objects and enters our eyes.
Light travels in a straight line until it enters our eyes.

Answers

Answer:

light reflects off the objects and enter our eyes

A apartie undergoes two displacement.The one has amagnitude of 150cm and makes an angle of 120 degrees with that positive x-axis.The resultant of the two displacement is 140cm at 35 degrees to the positive x-axis .Find the magnitude and direction of second displacement

Answers

Answer:

A = 150 cm at 120 degc

Where A + B = C       find B

B = C - A          add -A to both sides

Ax = 150 cos 60 = -75

Ay = 150 sin 60 = 129.9

Likewise

Cx = 114.7

Cy = 80.3

Bx = Cx - Ax = 114.7 + 75 = 189.7

By = Cy - Ay = 80.3 -129.9 = -49.6

B = (189.7^2 + 49.6^2)^1/2 = 196.7       length of B vector

tan B = By / Bx = -49.6 / 189.7       B = -14.65 deg

Also

sin B = By / B = -49.6 / 196.1 = -14.65 deg

So B is 196.1 cm at -14.65 deg

The 11 th one please! Somebody help me:(

Answers

Answer:

203360Pa

Explanation:

Pressure= density of liquid*height*g

=1000*10*10

=100000Pa

Total pressure= water pressure + atmospheric pressure

=1000000+103360

=203360 Pascal

what is velocity give its SI unit​

Answers

Answer:

Velocity is the speed of something given in a direction. the SI unit of velocity is metre per second or m/s.

Convert 400 mm to m using the method of dimensional analysis

Answers

Answer:

To convert 400 mm to m you can apply the formula [m] = [mm] / 1000; use 400 for mm. Thus, the conversion 400 mm m is the result of dividing 400 by 1000. 0.4

PLEASE MARK AS BRAINLIEST ANSWER

Who would most likely be required to work with sodium hydroxide?

Answers

Answer:

a plumber

Explanation:

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