What do you mean by Tribology? Explain its significance in our daily life 2. Explain the role played by friction and wear in a tribological system 3. How do you define Wear? How it affects the properties of a surface?

Answers

Answer 1
(1.)Tribology is the study of friction, wear, lubrication, and the design of bearings; the science of interacting surfaces in relative motion.
(2.)Tribology is particularly important in today's world because so much energy is lost to friction in mechanical components. To use less energy, we need to minimize the amount that is wasted. Significant energy is lost due to friction in sliding interfaces.
(3.) Wear can be defined as an extremely short sliding motion and is executed within a short time interval.
(Idk how it effects the properties of surface sorry )

Related Questions

what was the first dogs name that landed on the moon

Answers

Answer:

Laika

Explanation:

The dog's name was originally Kudryavka, or Little Curly, but she became known internationally as Laika, a Russian word for several breeds of dog similar to a husky. American reporters dubbed her Muttnik as a pun on Sputnik. Unfortunately, Laika's trip into space was one-way only.

Answer:

Laika

Explanation:

The dog is very cute buut it died i nearly cried

Edgar is walking 0.5 M/S toward the back of a train that is traveling forward at 6.0 M/S west. What is Edgars velocity relative to the ground?

Answers

Answer:

Just in 1 dimension  

Vpg = Vps + Vsg

Where

Vpg= relative to the ground

Vps= person relative to the ship

Vsg= ship relative to the ground

Vpg= Vps+Vsg ;

Vpg= 0.5 + 6  

Vpg= 6,5 m/s

A 1500 kg car on flat ground is moving 5.25 m/s. Its engine creates a 1250 N forward force as the car moves 42.8 m. What is its final velocity?​

Answers

Answer:

9.93 m/s

Explanation:

The following data were obtained from the question:

Mass (m) = 1500 Kg

Initial velocity (u) = 5.25 m/s

Force (F) = 1250 N

Distance (s) = 42.8 m

Final velocity (v) =...?

Next, we shall determine the acceleration of car. This can be achieved as shown below:

Force (F) = mass (m) x acceleration (a)

1250 = 1500 x a

Divide both side by 1500

a = 1250/1500

a = 0.83 m/s²

Therefore, the acceleration of the car is 0.83 m/s²

Now, we can determine the final velocity of car as shown below:

Initial velocity (u) = 5.25 m/s

Distance (s) = 42.8 m

Acceleration (a) = 0.83 m/s²

Final velocity (v) =...?

v² = u² + 2as

v² = (5.25)² + 2 x 0.83 x 42.8

v² = 27.5625 + 71.048

v² = 98.6105

Take the square root of both side

v = √98.6105

v = 9.93 m/s

Therefore, the final velocity of the car is 9.93 m/s

Answer:

9.93

Explanation:

too easy, just use a calculator lol

HELP ME PLEASE AND THANK UUU

Answers

Answer:

D.

Explanation:

Work is done when a force moves its point of application a distance in the direction of that force.

Work = force × distance.

What is the average speed of the tiger between the times t = 0s and t
= 12 s?
Choose 1 answer:
m
(A
6
S
m
B
-0.33
s
m
S
0.33
S

Answers

Answer:

A.6s

Explanation:

Average time=

[tex]average time \: t = \frac{t1 + t2}{2 } \\ \frac{0 + 12}{2} \\ \frac{ 12}{2} \\ t = 6s[/tex]

PLEASE ANSWER FOR BRAINLIEST!! A guitar string vibrates with a frequency of 4 kHz. What is the period of the waves in seconds?

Answers

Answer:

T = 0.00025 secs

Explanation:

Given:

Frequency = 4 kHz = 4000 Hz

Required:

Time Period = ?

Formula:

T = 1/f

Solution:

T = 1/4000

T = 0.00025 secs

Answer:

0.00025 seconds

Explanation:

Time period = 1 / frequency

= 1/4000

= 0.00025 seconds

Hope this helps, and please mark me brainliest if it does!

(d)
The circuit is connected for 300 s
The total current in the circuit stays at 0.56 A
Calculate the total charge flow.
Use the equation:
charge flow = current x time

Answers

Answer:

168

Explanation:

charge flow= current × time

Q. = 0.56 × 300

What is the role of a carburettor.​

Answers

(I think) it combines gasoline and air creating a highly combustible mixture

Which describes how to calculate density? mass divided by volume volume divided by mass mass added to volume volume subtracted from mass

Answers

Answer:

Mass divided to volume (D = M/V)

Explanation:

Its the formula :)

Answer:

A. mass divided by volume

Explanation:

The density formula is given as:

d=m/v

where m is the mass and v is the volume.

In this formula, the mass of an object is divided by its volume. Therefore, the correct answer is A. mass divided by volume.

John drives his car 120 miles east in 2 hours, 90 miles east in 1.5 hours, then he stops at the gas station for half an hour. He soon realizes that he has to go back 8 miles west which takes him one hour to reach his final destination. Calculate his average velocity during the entire time.

Answers

Answer: 44.9 m/s

Explanation:

Velocity = displacement/time

While displacement is the distance travelled in a specific direction.

The east direction will be positive while the west direction will be negative.

The total displacement will be :

120 + 90 - 8 = 202 miles

While the total time will be:

2 + 1.5 + 1 = 4.5 hours

Half hour time he used in the gas station will not be considered.

Average Velocity = total displacement ÷ total time.

Average velocity = 202/4.5

Average velocity = 44.89 m/s

Average velocity through out the entire time is 44.9 m/s

1) Which one of the following is vector,
B) Momentum
C) Mass
A) Energy
D) Temperature​

Answers

Answer:

momentum is a vector quantity that points in the same direction as velocity

Explanation:

Look at figure D . Explain what will happen if a larger mass it put on the force meter

Answers

it will experience great force

Please helpppp: A caterpillar tries to climb straight up a wall two meters high, but for every 2 cm up it climbs, it slides down 1 cm.

Eventually, it reaches the top. When it reaches the top, it does not pull itself over so it will slide down 1 cm.

In the first box, select the total displacement. In the second box, indicate the direction.

cm

Answers

Answer:

The caterpillar is climbing a wall of 2 meters.

the caterpillar climbs 2 cm, and then falls 1 cm, so for each "climb", the caterpillar actually moves 1cm, while the actual distance moved is 3 cm, the displacement is 1cm.

Remember, displacement is equal to the difference between the initial position and the last position.

Now, when the caterpillar reaches the top, it slides down one centimeter, so the final position of the caterpillar is:

2 meters - 1 centimeter, and 1 m = 100 cm

200 centimeters - 1 centimeter = 199 centimeters.

Knowing that the caterpillar started at the ground, at 0 centimeters, then we can find that the difference between the final position and the initial position is:

D = 199cm - 0cm = 199cm

The displacement is 199cm.

The direction is upwards, if we define the y-axis as the vertical axis, the the direction is in the positive y-axis.

a solid weighs 18.36N on the surface of the moon. The force of gravity on the moon is 1.7Nkg-1. Determine the mass of the solid​

Answers

Answer:

mass of the solid is 10.8kg

Explanation:

Weight of the solid=w=18.36N

Force of gravity on the surface of the moon=g=1.71Nkg^-1

Mass of the solid on the moon=m=?

as we know that

weight=mass×force of gravity

here we have to find the mass

[tex]\frac{weight}{force of gravity}[/tex]=mass

mass=[tex]\frac{18.36N}{1.7Nkg^-1}[/tex]

Mass of the solid=10.8kg

i hope it will help you

The density of pine is generally about 0.5 g/cm3. What is the mass of a 800 cm3 piece of pine

Answers

Answer:

400grams

Explanation:

Mass is density × volume

0.5×800= 400 grams

Mass is density × volume

0.5×800= 400 grams.

What does density mean?

Density is the number of things—which could be people, animals, plants, or objects—in a certain area. To calculate density, you divide the number of objects by the measurement of the area. The population density of a country is the number of people in that country divided by the area in square kilometers or miles.

How do we calculate density?

density, the mass of a unit volume of a material substance. The formula for density is d = M/V, where d is density, M is mass, and V is volume.

Learn more about density here:  https://brainly.com/question/1354972

#SPJ2

Need Help !
A 1500 kg car on flat ground is
moving 5.25 m/s. Its engine
creates a 1250 N forward force as the car moves 42.8 m. What is its final velocity?​

Answers

Answer: 5.96m/s

Explanation:

Given the following :

Mass of car (m) = 1500kg

Velocity (V) = 5.25m/s

Forward force of engine = 1250N

Diatance moved = 4.8m

Final Velocity =?

Final kinetic energy = Initial kinetic energy + work done by engine

Initial kinetic energy = 0.5 × mass × velocity^2

Initial kinetic energy = 0.5 × 1500 × 5.25^2

Initial kinetic energy = 20671.875 J

Work done by engine = Force × distance

Work done by engine = 1250 × 4.8 = 6000J

Final kinetic energy = (20671.875 + 6000) J

= 26671.875 J

From kinetic energy = 0.5mv^2

26671.875 = 1/2 × 1500 × v^2

53343.75 = 1500v^2

v^2 = 35.5625

v = sqrt(35.5625)

v = 5.96m/s

An aluminum bar 600mm long, with diameter 40mm long has a hole drilled in the center of the bar.The hole is 30mm in diameter and is 100mm long. If modulus of elasticity for the aluminum is 85GN/m2.Calculate the total contraction on the bar due to a compressive load in 180KN

Answers

Answer:

Total contraction on the Bar  = 1.22786 mm

Explanation:

Given that:

Total Length for aluminum bar = 600 mm  

Diameter for aluminum bar  = 40 mm

Hole diameter  = 30 mm

Hole length = 100 mm

elasticity for the aluminum is 85GN/m² = 85 × 10³ N/mm²

compressive load P = 180 KN = 180  × 10³ N

Calculate the total contraction on the bar = ???

The relation used in  calculating the contraction on the bar is:

[tex]\delta L = \dfrac{P *L }{A*E}[/tex]

The relation used in  calculating the total contraction on the bar can be expressed as :

Total contraction in the Bar = (contraction in part of bar without hole + contraction in part of bar with hole)

i.e

Total contraction on the Bar = [tex]\dfrac{P *L_1 }{A_1*E} + \dfrac{P *L_2 }{A_2 *E}[/tex]

Let's find the area of cross section without the hole and with the hole

Area of cross section without the hole is :

Using A = πd²/4

A = π (40)²/4

A = 1256.64 mm²

Area of cross section with the hole is :

A = π (40²-30²)/4

A = 549.78 mm²

Total contraction on the Bar = [tex]\dfrac{P *L_1 }{A_1*E} + \dfrac{P *L_2 }{A_2 *E}[/tex]

Total contraction on the Bar  = [tex]\dfrac{180 *10^3 \N }{85*10^3 \ N/mm^2} [\dfrac{500}{1256.64}+ \dfrac{100}{549.78}][/tex]

Total contraction on the Bar  = 2.117( 0.398 + 0.182)

Total contraction on the Bar  = 2.117*(0.58)

Total contraction on the Bar  = 1.22786 mm

Which type of motion does a spinning ball have as it rolls along a curved path?

Answers

Answer:

The ball is going to be spinning in a clockwise direction.

b) Which device is used to measure the weight of a body?
Physical balance
Spring balance
Beam balance
Top-pan balance​

Answers

Answer:

beam balance

Explanation:

its the most optimal

A reheat Rankine cycle operates with water as the working fluid. Steam enters the first turbine at 8 MPa and 450°C and exits at 0.8 MPa. It is then reheated to 400°C before entering the second turbine, where it exits at 10 kPa. If the amount of work into the pump is 8.04 kJ/kg and the net work per cycle produced is 1410.25 kJ/kg, determine the thermal efficiency of the cycle

Answers

Answer:

The thermal efficiency, [tex]\eta _{reheat}[/tex], of the Rankine cycle with reheat is 36.81%

Explanation:

p₁ = 8 MPa = 80 Bars

T₁ = 450°C = 723.15 K

From steam tables, we have;

v₁ = 0.0381970 m³/kg

h₁ = 3273.23 kJ/kg

s₁ = 6.5577 kJ/(kg·K) = s₂

The p₂ = 0.8 MPa

T₂ = Saturation temperature at 0.8 MPa = 170.414°C = 443.564 K

h₂ = 2768.30 kJ/kg

[tex]T_{2'}[/tex] = 400°C = 673.15 K

[tex]h_{2'}[/tex] = at 400°C and 0.8 MPa = 3480.6 kJ/kg

p₃ = 10 kPa = 0.1 Bar

T₃ = Saturation temperature at 10 kPa = 45.805 °C = 318.955 K

h₃ = 2583.89 kJ/kg

h₄ = [tex]h_{3f}[/tex] = 191.812 kJ/kg

The thermal efficiency, [tex]\eta _{reheat}[/tex], of a Rankine cycle with reheat is given as follows;

[tex]\eta _{reheat} = \dfrac{\left (h_{1}-h_{2} \right )+\left (h_{2'}-h_{3} \right )-W_{p}}{h_{1}-\left (h_{4}+W_{p} \right )+\left (h_{2'}-h_{2} \right )}[/tex]

Therefore, we have;

[tex]\eta _{reheat} = \dfrac{(3273.23 -2768.30 ) + (3480.6 -2583.89 ) - 8.04)}{(3273.23 -(191.812 + 8.04) + (3480.6 -2768.30 ) } = 0.3681[/tex]

Which in percentage is 36.81%.

A baseball pitcher loosens up his pitching arm. He tosses a 0.20-kg ball using only the rotation of his forearm, 0.28 m in length, to accelerate the ball. What is the moment of inertia of the ball alone as it moves in a circular arc with a radius of 0.28 m?

Answers

Answer:

Moment of Inertia, I = 0.016 kgm²

Explanation:

Mass of the ball, m = 0.20 kg

Length of the pitcher's arm, l = 0.28

Radius of the circular arc, r = 0.28 m

Moment of Inertia is given by the formula:

I = mr²

I = 0.20 * 0.28²

I = 0.20 * 0.0784

I = 0.01568

I = 0.016 kgm²

Can a body move with a certain velocity in the direction of the east have acceleration in the direction of the west?

Answers

Answer:
Yes, a body with a certain velocity can have an opposite acceleration, the acceleration would then be negative, since it is opposite to the direction to the velocity and also because the direction in which the acceleration is portrayed is on the left-hand side.

Hope this answer helps :)

what is the conservation of momentum?​

Answers

Conservation of momentum is collisions between two objects, but only to an isolated system of objects (a system that is not acted on by force external to the system)

Hope this helps :)
Ps sorry it’s so technical

The estimated distance of the earth from the sun is 149000000km. The speed of the light is 300000km/s. What is the time taken for the light to travel from the sun to the earth

Answers

Answer:

The time taken for the light to travel from the earth to the sun = 496.67 seconds

Explanation:

Estimated distance of the earth to the sun = 149000000km

Speed of light =  300000km/s

Time taken for the light to travel from the sun to the earth = ?

Speed = Distance/time

time = Distance/speed

time = 149000000/300000

time = 496.67 s

The time taken for the light to travel from the earth to the sun = 496.67 seconds

when light passess from air into glass the angle of incidence is always _______ the angle of refraction

Answers

Explanation:

The angle of incidence is always smaller than the angle of refraction

Kelvin is the base unit of which pysical quantity?

Answers

Answer:Temperature

About physical quantities:

Those quantities which can be measured directly or indirectly is called physical quantities.

There are two types of physical quantities.They are:

fundamental quantity

Those quantity which are not dependent upon any quantity are called fundamental quantity.for eg: length,mass time etc.

Derived Quantity

Those quantity which are dependent upon other quantities are called derived Quantity. for eg: volume,area etc.

About temperature:

Temperature is the degree of hotness and coldness of a body.Temperature is measured in degree,Celsius,degree Fahrenheit or Kelvin scale.Temperature is measured by using thermometer.

Hope this helps....

Good luck on your assignment.....

Answer:

Thermodynamic temperature

Explanation: Research states that ;

Thermodynamic temperature is the measure ( absolute)  of temperature and is one of the principal parameters of thermodynamics.

It uses the kelvin scale for measurement and selects the triple point of water at 273.16 K as the fundamental fixing point.

What is conduction? Please help. First answer will mark Brainliest

Answers

Answer:

Conduction is the main method of thermal energy transfer in solids.

Hope this helps.....

Answer:

conduction is the transfer of thermal energy through direct contact

HELLLP PLEASE || the graph below shows a conversion of energy for a skydive jumping out of a plane and landing safely on the ground. which energy is represented by line A? A) Potential B) Thermal C) Kinetic D) Total Energy

Answers

Answer: I maybe wrong but i'm pretty sure its C) Kinetic energy

Transverse waves on a string have wave speed v=8.00 m/s, amplitude A=0.0700m, and direction, and at t=0 the x-0 end of the wavelength -0.320m. The waves travel in the -x string has its maximum upward displacement. a) Find the frequency, period and wave number of these waves b) Write a wave function describing the wave c) Find the transverse displacement of a particle at x=0.360m at time t=0.150 d) How much time must elapse from the instant in part (c) until the particle at x-0.360 m next has maximum upward displacement?

Answers

Answer:

a. frequency = 25 Hz, period = 0.04 s , wave number = 19.63 rad/m

b. y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]

c.  0.0496 m

d. 0.03 s

Explanation:

a. Frequency, f = v/λ where v = wave speed = 8.00 m/s and λ = wavelength = 0.320 m

f = v/λ = 8.00 m/s ÷ 0.320 m = 25 Hz

Period, T = 1/f = 1/25 = 0.04 s

Wave number k = 2π/λ = 2π/0.320 m = 19.63 rad-m⁻¹

b. Using y = Asin(kx - ωt) the equation of a wave

where y = displacement of the wave, A = amplitude of wave = 0.0700 m and ω = angular speed of wave = 2π/T = 2π/0.04 s = 157.08 rad/s

Substituting the variables into y, we have

y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]

c. When x = 0.360 m and t = 0.150 s, we substitute these into y to obtain

y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]

y = (0.0700 m)sin[(19.63 rad/m × 0.360 m) - (157.08 rad/s × 0.150 s)]

y = (0.0700 m)sin[(7.0668 rad) - (23.562 rad)]

y = (0.0700 m)sin[-16.4952 rad]

y = (0.0700 m) × 0.7084

y = 0.0496 m

d. For the particle at x = 0.360 m to reach its next maximum displacement, y = 0.0700 m at time t. So,

y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]

0.0700 m = (0.0700 m)sin[(19.63 rad/m × 0.360 m) - (157.08 rad/s)t]

0.0700 m = (0.0700 m)sin[(7.0668 rad - (157.08 rad/s)t]  

Dividing through by 0.0700 m, we have

1 = sin[(7.0668 rad - (157.08 rad/s)t]

sin⁻¹(1) = 7.0668 rad - (157.08 rad/s)t  

π/2 = 7.0668 rad - (157.08 rad/s)t

π/2 - 7.0668 rad = - (157.08 rad/s)t

-5.496 rad = - (157.08 rad/s)t

t = -5.496 rad/(-157.08 rad/s) = 0.03 s

The frequency of the wave is 25 Hz, the period is 0.04 s, and the wave number of the given wave is 19.63 rad/m.

(A) Frequency of the wave,

[tex]\bold {f = \dfrac v{\lambda}}[/tex]

where

v - speed = 8.00 m/s

λ - wavelength = 0.320 m

[tex]\bold {f = \dfrac {8.0 m/s }{0.32\ m} = 25\ Hz}[/tex]

Period of the wave,

[tex]\bold {T = \dfrac 1f = \dfrac 1{25 } = 0.04\ s }[/tex]

Wave number of the wave,

[tex]\bold {k = \dfrac {2\pi }{\lambda} = \dfrac {2\pi }{0.320} = 19.63\ rad\ m^{-1}}[/tex]

(B)

Wave function equation of a wave,

y = A sin (kx - ωt)

where

y - displacement of the wave

A = amplitude  = 0.0700 m

ω = angular speed  = 2π/T = 2π/0.04 s = 157.08 rad/s

Put the values in the formula,

y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]

(C) When x = 0.360 m and t = 0.150 s,

y = (0.0700 m)sin[(19.63 rad/m × 0.360 m) - (157.08 rad/s × 0.150 s)]

y = 0.0496 m

Therefore, the frequency of the wave is 25 Hz, the period is 0.04 s, and the wave number of the given wave is 19.63 rad/m.

To know more about waves,

https://brainly.com/question/3004869

An 18-kg bicycle carrying a 62-kg girl is traveling at a speed of 7 m/s. What is the kinetic energy of the girl
and bicycle combined together?​

Answers

Answer:

1960 J

Explanation:

EK = (18 kg + 62 kg)[tex](7.0 m/s)^{2}[/tex]/2 = 1960 J

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