Is velocity ratio of a machine affected by applying oil on it?Explain with reason. ​

Answers

Answer 1

Answer:

It depends upon SAE No. of oil. (SAE means Society of Automotive Engineers). However, it usually does protect against friction.

Explanation:

If we use very viscous oil, it does not reach all the parts. Very thin oil will flows away easily and gets wasted. Grease is used in such cases. It is generally used around ball-bearing. Normal grease or oil is never used where there is high pressure, high temperature and high speed. Special lubricants are used in such cases. In cold season the oil becomes thick and in hot season it becomes thin. Therefore selection of lubrication also depends on the season. It is always advisable to refer operating manual of the equipment before selecting the lubricant.

The intensity of friction depends on following factors:

i) The area involved in friction.

ii) The pressure applied on the surfaces.

Force = Pressure ´ Area Frictional force will increase, if the area of contact will increase or if pressure applied on the surface increased.


Related Questions

In isoelectric focusing gel electrophoresis a. there is a pH gradient that parallels the electric field gradient b. particular care must be taken to ensure the same pH along the length of the gel c. the electric current is allowed to fluctuate d. the electric circuits of the apparatus must be very well insulated

Answers

Answer:

a. there is a pH gradient that parallels the electric field gradient.

Explanation:

Gel electrophoresis is a technique used to separate DNA fragments according to their size. DNA samples are loaded in the wells and then electric current is applied to pull the DNA fragments out from the gel. Isoelectric gel electrophoresis is a process in which negatively charged DNA fragments are separated from the gel.


2) Define volume. Explain in detail how can volume of irregular object be determined?

PLZ HELP NEED THIS RN

Answers

The three dimensional space of a body is called volume

out of solid and liquid which has more effect on gravitation​

Answers

Answer:

The effect of gravitation is more in liquid than on solid because inter molecular force of attraction is less in liquid and it is weak than that of solid. ... Whereas in solid the molecule are densely packed together an the inter molecular forces are constantly acting upon one another, this results in higher forces.

a.
quuntlity.
Answer the following questions.
What is force? Write down its SI unit.
b. Name
any five types of force.
c.
What is pulling force? Give any two examples.
d. What is centripetal force? Give one example of centrifugal force.
What is gravitational force? Give two examples.
f. What is magnetic force? How is this force useful to us?

Answers

Answer:

1) Force is the action of pull or push that changes or tends to change the position of a body. Its SI unit is newton.

2) The types of force are:

• Pulling and Pushing force

• Frictional force

• Gravitational force

•Muscular force

• Centripetal and Centrifugal force

What are the units for speed?
O A. km/s2
O B. m/s2
O C. m/s2
O D. m/s

Answers

Answer:

Explanation:

The only one that doesn't have a time unit that is squared is the one that is a label for speed or velocity. Acceleration has a label with the time unit squared, like m/s/s. Choice D is the only unit for speed/velocity.

Answer: D

Explanation: metres per second (m/s)

Write down the conservation of momentum?​

Answers

Law of conservation of momentum states that when two objects collide with each other , the sum of their linear momentum always remains same or we can say conserved and is not effected by any action, reaction only in case is no external unbalanced force is applied on the bodies.
Let,
m
A

= Mass of ball A
m
B

= Mass of ball B
u
A

= initial velocity of ball A
u
B

= initial velocity of ball B
v
A

= Velocity after the collision of ball A
v
B

= Velocity after the collision of ball B
F
ab

= Force exerted by A on B
F
ba

= Force exerted by B on A
Now,
Change in the momentum of A= momentum of A after the collision - the momentum of A before the collision
= m
A

v
A

−m
A

u
A


Rate of change of momentum A= Change in momentum of A/ time taken
=
t
m
A

v
A

−m
A

u
A




Force exerted by B on A (F
ba

);
F
ba

=
t
m
A

v
A

−m
A

u
A



........ [i]
In the same way,
Rate of change of momentum of B=
t
m
b

v
B

−m
B

u
B




Force exerted by A on B (F
ab

)=
F
ab

=
t
m
B

v
B

−m
B

u
B



.......... [ii]
Newton's third law of motion states that every action has an equal and opposite reaction, then,
F
a

b=−F
b

a [ ' -- ' sign is used to indicate that 1 object is moving in opposite direction after collision]

Using [i] and [ii] , we have
t
m
B

v
B

−m
B

u
B



=−
t
m
A

v
A

−m
A

u
A




m
B

v
B

−m
B

u
B

=−m
A

v
A

+m
A

u
A


Finally we get,
m
B

v
B

+m
A

v
A

=m
B

u
B

+m
A

u
A


This is the derivation of conservation of linear momentum.

Algunos estudiantes de tu promoción consideran que se debería aumentar el número de horas semanales de Educación Física. Otros consideran que el número de horas debería mantenerse. Escribe un artículo de opinión en el que presentes tu punto de vista sobre este tema y al menos tres razones que justifiquen tu postura. Tu artículo se publicará en el periódico escolar La Voz.
una ayuda plis :c

Answers

La respuesta correcta para esta pregunta abierta es la siguiente.

Te compartimos las tres ideas que te pueden ayudar para hacer tu artículo.

Título:

La Educación Física, una prioridad para las escuelas.

Existe una frase milenaria que se le atribuye a los griegos que dice "Mente sana en cuerpo sano."

Y es muy cierta.

Las escuelas deberían considerar seriamente aumentar el número de horas semanales para la impartición de la educación física por las siguientes razones.

1.- La educación física es vital para el desarrollo físico del estudiante. Desde los grados más básicos, las escuelas deberían fortalecer la enseñanza de la educación física por motivos de salud, y dejar este buen hábito en los alumnos para toda la vida.

2.- La educación física, mejora el rendimiento académico ya que ayuda oxigenando los músculos, fortaleciendo el cerebro para que pueda concentrase mejor, despeja a los alumnos de tal forma que puedan regresar a los salones e clase más "despiertos."

3.- La educación física sirve para introducir la importancia de practicar deporte toda la vida, y hacerlo en la etapa escolar a través de equipos deportivos como el Futbol Americano, el beisbol, el basquetbol, el volibol, el soccer, y otros tantos.

Este idea del trabajo en equipo a través del deporte es muy importante para desarrollar habilidades como el liderazgo, el compromiso, la constancia y el superar la adversidad.

El profesor de educación física debe enseñarte la forma correcta de respirar cuando haces ejercicio, la importancia de la relajación del cuerpo para iniciar una actividad. El profesor debe hacer énfasis en la etapa del calentamiento y el estiramiento para preparar al cuerpo antes de realizar el ejercicio. Así como muchas otras enseñanzas.

Por esa razón, las escuelas deberían considerar seriamente la posibilidad de aumentar las horas de educación física por semana.

Electricity flows from
positive to positive
negative to positive
negative to negative
positive to negative

Answers

Answer:

is it from positive to negative am I right tell me if I am wrong

Answer:

positive to negative

The flow of electric current is similar to the flow of water which is from higher level to lower level.

The electric current flow from higher potential region(positive* low concentration of electron) to lower potential region(negative*high concentration of electron)

Please help me with these I might need more than only 1 person to answer ​

Answers

Explanation:

a) copper

b) olive oil

Hope it helps✌✌

balance the following equations: CUCO3+H2SO4- CUSO4+H2O+CO2​

Answers

Answer:

It is already balanced

Explanation:

It is already balanced

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

Lightning a. occurs when a positively charged cloud base induces a negative charge on the Earth's surface. b. travels most often from cloud to ground and cannot travel from cloud to cloud. c. may be accompanied by the sound of explosively expanding hot air, called thunder. d. involves a conductive path or leader of positive ions from cloud to ground.

Answers

Answer:

c. may be accompanied by the sound of explosively expanding hot air, called thunder.

Explanation:

Lightning is a discharge which is due to the reaction between oppositely charged charges in the clouds, or between clouds base and the Earth surface.

The motion of the cloud causes charging of clouds by friction, thus the reaction between opposite charges (jumping of charges from one cloud to another) in the cloud can lead to lightning. Also, oftentimes the bottom of a cloud is negatively charged so that this is attracted to the positive charge on the earth surface. Thus leading to a discharge called lightning.

Thus in the given question, the appropriate option is C. This implies that, lightning may be accompanied by the sound of explosively expanding hot air, called thunder.

Động vật nào sau đây máu đi nuôi cơ thể không pha trộn giữa máu giàu O2 và máu giàu CO2?

A.
Bò sát, chim, thú

B.
Cá, bò sát, chim

C.
Cá, lưỡng cư, bò sát

D.
Cá, chim, thú

Answers

Answer:

D

Explanation:

Cá xương, chim, thú, cá sấu không có sự pha trộn máu giàu O2 và máu giàu CO2 ở tim vì tim cá có 2 ngăn, tim các loài chim, thú, cá sấu có 4 ngăn

A car has a mass of 2000 kg. While it is traveling along a perfectly flat road, it goes around an unbanked turn that has a radius of 40.0 m. The coefficient of static friction between the car tires and the road is 0.500. The car travels successfully around the turn at a constant speed of 10.0 m/s. Calculate the magnitude of the car's acceleration as it goes around the turn. _______ m/s^2

Answers

Answer:

2.5 m/s²

Explanation:

The given parameters are;

The mass of the car, m = 2,000 kg

The radius of the car, r = 40.0 m

The coefficient of friction between the car tires and the road, μ = 0.500

The constant speed with which the car moves, v = 10.0 m/s

The normal reaction of the road on the car, N = The weight of the car;

∴ N = m × g

Where;

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

N ≈ 2,000 kg × 9.81 m/s² = 19,620 N

The frictional force, [tex]F_f[/tex] = μ × N

The centripetal force, [tex]F_c[/tex] = m·v²/r

The car moves without slipping when [tex]F_f[/tex] = [tex]F_c[/tex]

Therefore, [tex]F_f[/tex] = 0.500 × 19,620 N = 2,000 kg × [tex]v_{max}[/tex]²/40.0 m

∴ [tex]v_{max}[/tex] = √(0.500 × 19,620 N × 40.0 m/2,000 kg) ≈ 14.007 m/s

Therefore, the velocity with which the car moves, v < [tex]v_{max}[/tex]

The cars centripetal acceleration, [tex]a_c[/tex] = v²/r

∴ [tex]a_c[/tex] = (10.0 m/s)²/40.0 m = 2.5 m/s²

The cars centripetal acceleration as it goes round the turn, [tex]a_c[/tex] = 2.5 m/s².

please answer fast..........​

Answers

Answer:

The correct answer is a. Subsonic

Hope this helps you^_^

Please mark as Brainliest.

Yea your answer is subsonic wave I hope this help

Define derived unit with example​

Answers

Answer:

A derived unit is a SI unit of measurement comprised of a combination of the seven base units. Like SI unit of force is the derived unit, newton or N where N=s21×m×kg. There are some commonly used derived units which includes: 1. Pressure = AreaForce=m2N.

Explanation:

Please help








I can’t get this right

Answers

Answer:

6,76 x 10^-7 T.

Explanation:

The Magnetic field formula for a wire is B=(μ x I)/2πd , where μ (=4π x 10^-7 Tm/A) is the permeability, I is the current and d is the distance.

matter can enter and exit which of the following systems?
A. isolated only
B. open only
C. both open and isolated
D. Both closed and isolated

Answers

D will be the correct answer
If I am right
The answer is B open only

The spectra of most galaxies show redshifts. This means that their spectral lines Group of answer choices always are in the red part of the visible spectrum. have wavelengths that are longer than normal. have a higher intensity in the red part of the spectrum. have wavelengths that are shorter than normal.

Answers

have a higher intensity in the red part of the spectrum

Because of the Doppler effect, the spectra of most galaxies show redshifts. This means that their spectral lines Group of answer choices always are in the red part of the visible spectrum

Most galaxies' spectra have been redshifted, which means that their spectral lines are now pushed away from their normal or rest wavelengths and towards longer wavelengths. When an object travels away from an observer, the Doppler effect causes the shift phenomenon.

The Big Bang hypothesis and the concept of the expanding universe, show that galaxies are moving away from us, observed from the redshift lines.

The waves' apparent wavelengths shift as a result, changing the color of light waves or the pitch of sound waves.

Hence, because of the Doppler effect, the spectra of most galaxies show redshifts. This means that their spectral lines Group of answer choices always are in the red part of the visible spectrum.

To learn more about the Doppler effect, here:
https://brainly.com/question/28106478

#SPJ6

why does apparent depth of different liquids vary

Answers

It’s due to the refraction of light rays as they traverse the boundary between water and air. The greater the viewing angle, the more the bending of the light and therefore the less the apparent depth. An object placed in a denser medium, when viewed from rarer medium appears to be at a lesser depth than its real depth due to refraction of light.

PLEASE HELP MAX POINTS AND BRAINLIEST!
Look at the graph below.

A graph is shown with Absolute magnitude shown on the y-axis and Surface temperature in degree Celsius shown on the x-axis. The Dwarf stars are shown along a slanting line from coordinates 30,000 and minus 3 to 10,000 and minus 4. The Main Sequence stars are shown along a slanting line from coordinates 20,000 and minus 2 to 2,000 and minus 6. The giants are shown along a line parallel to the x-axis from coordinates 5,000 and 2 to 2,000 and 3. The supergiants are shown along a line parallel to the x-axis from coordinates 7,500 and 4 to 2,500 and 4. Point A has coordinates 20,000 and minus 4. Point B has coordinates 2,500 and minus 4. Point C has coordinates 5,000 and 2. Point D has coordinates 7,000 and 4.

Which of the following stars is most likely to be red?
a. Star A
b. Star B
c. Star C
d. Star D

Answers

i believe it would be Star A since Point A is a dwarf star and dwarf stars are usually most likely to have red coloring

Answer:

Star A

Explanation:

Literally the question has provided the answer itself

Calculation not required.

See the wordings

First star is dwarf star .

Dwarf star is mostly reddish brown or red colored .

Hence star A is the answer

Please please helpjejejnebwbww​

Answers

Answer:

C. 540 N

Explanation:

Let suppose that system formed by the athlete and the load are in equilibrium. By Newton's Laws of Motion, we use the moment equation with respect to the feet of the athlete to determine the upward force exerted by his two arms:

[tex]\Sigma M = -F\cdot r_{1} + m_{L}\cdot g \cdot r_{2} + m_{A}\cdot g \cdot r_{3} = 0[/tex]

[tex]F = \frac{(m_{L}\cdot r_{2} + m_{A}\cdot r_{3})\cdot g}{r_{1}}[/tex] (1)

Where:

[tex]m_{L}[/tex] - Mass of the load, in kilograms.

[tex]m_{A}[/tex] - Mass of the athlete, in kilograms.

[tex]g[/tex] - Gravitational acceleration, in meters per square second.

[tex]r_{1}[/tex], [tex]r_{2}[/tex], [tex]r_{3}[/tex] - Distances with respect to the feet, in meters.

[tex]F[/tex] - Upward force exerted by his two arms, in newtons.

If [tex]m_{L} = 6\,kg[/tex], [tex]r_{2} = 1.20\,m[/tex], [tex]m_{A} = 70\,kg[/tex], [tex]r_{3} = 0.90\,m[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]r_{1} = 1.30\,m[/tex], then the upward force is:

[tex]F = \frac{[(6\,kg)\cdot (1.20\,m)+(70\,kg)\cdot (0.90\,m)]\cdot \left(9.807\,\frac{m}{s^{2}} \right)}{1.30\,m}[/tex]

[tex]F = 529.578\,N[/tex]

The upward force exerted by his two arms is 529.578 newtons. (Right answer: C)

Describe an experiment to find the volume of an irregular- shaped ston

Answers

One way to measure the volume of any irregular object (in your case, a stone) is to submerge it completely under water and measure the change in the height of the water level. This change in the water level (let's say it goes from 50 mL to 65 mL) indicates that the stone has a volume of 15 mL .

what is field selection process

Answers

Answer:

It is a process of offering jobs to desired candidates and offering jobs to the desired applicant.

Write the dimension of a / b in the x = at + bt2. Where x is the distance and t is the time?​

Answers

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

state any two effects of gravitational force ​

Answers

Answer:

The effect of gravity extends from each object out into space in all directions, and for an infinite distance. However, the strength of the gravitational force reduces quickly with distance. Humans are never aware of the Sun's gravity pulling them because the pull is so small at the distance between the Earth and Sun.

Answer:

The Earth's gravitational force accelerates objects when they fall. It constantly pulls, and the objects constantly speed up.

Explanation:

Describe the laws of liquid pressure and explain the term fluid. (Please try to give the correct answer 'coz it's urgent!)​

Answers

Answer:

The laws of liquid pressure are: ... The liquid pressure at a point inside the liquid is same in all directions. The liquid pressure at a point inside the liquid is directly proportional to the depth of that point from the free surface of liquid. The pressure of liquid at same depth is different for different liquids

Answer:

The laws of liquid pressure:

The pressure that is inside the liquid rises with the intensity from the surface of a liquid.

The term fluid:

Fluid is basically liquid and a substance that is known to have no certain shape. The opposite of the term fluid would be solid.

A rocket travels 1.3 km in 62 ms. What is its average speed in m⋅s−1? Do not give your answer in scientific notation. The answer should be given to 2 significant figures.

Answers

Answer:

Average speed = 0.35 m/s

Explanation:

Given the following data;

Distance = 1.3 Km

Time = 62 minutes

To find the average speed in m/s;

First of all, we would convert the quantities to their standard unit (S.I) of measurement;

Conversion:

1.3 kilometres to meters = 1.3 * 1000 = 1300 meters

For time;

1 minute = 60 seconds

62 minutes = X

Cross-multiplying, we have;

X = 62 * 60

X = 3720 seconds

Now, we can calculate the average speed in m/s using the formula;

[tex] Speed = \frac {distance}{time} [/tex]

[tex] Speed = \frac {1300}{3720} [/tex]

Average speed = 0.35 m/s

In a hydrogen atom, the electric force is the centripetal force. Determine the speed of an electron in orbit around a proton if the distance between them is 5.29 x 10^{-11} m. The mass of an electron is 9.11 x 10^-31 kg. (HINT: equate centripetal force and electric force)

Answers

Answer: 9.11, 8^90
hope this helps

explain why resistors connected in parallel are called current dividers​

Answers

Explanation:

A parallel circuit is often called a current divider for its ability to proportion—or divide—the total current into fractional parts. Once again, it should be apparent that the current through each resistor is related to its resistance, given that the voltage across all resistors is the same

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