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.
What is the connection of H ions at a ph=2?
Answer:
Explanation:
High concentrations of hydrogen ions yield a low pH (acidic substances), whereas low levels of hydrogen ions result in a high pH (basic substances). The overall concentration of hydrogen ions is inversely related to its pH and can be measured on the pH scale
Một người đi xe ô tô từ a đến b cách nhau 90km trong nửa quãng đường đầu người dó đi với vận tốc v1 trong nửa quãng đường sau người đó đi với vận tốc v2=2v1/3.Tính vận tốc của người đó trên mỗi chặng đường để sau 1.5h người đó đi đến b
Answer:
The speed of the first half is 75 km/h and for the second half is 50 km/h.
Explanation:
A person driving a car from a to b 90km apart for the first half of the distance travels with speed v1 the second half of the distance travels with a speed of v2=2v1/3. Calculate his speed per each the distance so that after 1.5 hours that person reaches b
Total distance, D = 90 km
Let the time for he first half is t and for the second half is t'.
Distance = speed x time
45 = v1 x t .... (1)
And
45 = v2 x t' .... (2)
Total time is T = t + t'
[tex]1.5 = \frac{45}{v_1}+\frac{45}{v_2}\\\\1.5 = \frac{45}{v_1}+\frac{3\times 45}{2v_1}\\\\1.5 = \frac{90+135}{2v_1}\\\\3v_1 = 225 \\\\v_1 = 75 km/h[/tex]
Now, v2 = 2 x 75/3 = 50 km/h
Describe an experiment to find the volume of an irregular- shaped ston
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 .
out of solid and liquid which has more effect on gravitation
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. Tick (1) the best alternatives. 1. What is the acceleration due to gravity on the surface of moon ? (a) 9.8m/s (b)1.6m/s2 (c) 6.67x10-1m/s (d) 9.8m/s?
Answer:
[tex] \green{ \sf \: \: 1.6 \: m {s}^{ - 2} \: \: \: is \: the \: correct \: answer}[/tex]
Explanation:
[tex] \sf \: \huge{g } _{ \small{moon}} = \frac{ {\huge{g}}_{earth}}{6} \\ \\ \sf \implies \: \sf \: \huge{g } _{ \small{moon}} = \frac{ 9.8}{6} = 1.6 \: \: m {s}^{ - 2} [/tex]
How long can a tow rope or chain be?
1. 20 feet 2. 15 feet
3. 5 feet
4. 10 feet
Answer:
"For towing, a tow chain should be of a length that keeps both vehicles within the maximum 4.5 meter distance, also tow chains an be any length 20 foot chains are often chosen"
Explanation:
- https://letstowthat.com
Also Quick note the feet of tow rope or chain varies on the situation but most longest or 20 feet.
what will happen to the gravition force between two bodies if the distance between them is halved keeping their masses constant
Answer:
The new force will be 4times the original
which of the following containing same amount of boiling hot water is likely to cool first and why? a. a breaker whose surface is covered with aluminum foil b. a breaker whose surface is painted black
como previene un diafragma el embarazo
Answer:
Un diafragma es una pieza de silicona o de goma reutilizable que cubre el cuello del útero. El diafragma se coloca dentro de la vagina con espermicida antes de tener relaciones sexuales para prevenir un embarazo. El diafragma es un dispositivo anticonceptivo que impide que los espermatozoides ingresen en el útero.
make a list of principle of lever.
Answer:
The force applied to make the object move
Answer:
input work = output work
E * ED = L* LD
Explanation:
The principle of lever is that input work is always equal to output work .
when you go out to your car one cold winter morning you discover a 0.80 cm thick layer of ice on the windshield which has an area of 1.4m square if the temperature of the ice is - 2.0 degrees celsius and its density is 917 kg/m to the third find the heat required to melt all the ice
Answer:
The total heat required to melt the ice is approximately 3.473 MJ
Explanation:
The given parameters for the layer of ice are;
The thickness of the layer of ice, t = 0.80 cm = 0.008 m
The area of the wind shield, A = 1.4 m²
The initial temperature of the ice, T₁ = -2.0 °C = 271.15 K
The density of the ice, ρ = 917 kg/m
The temperature at which ice melts, T₂ = 0 °C = 273.15 K
We have;
The mass of the ice, m = ρ × t × A
∴ m = 917 kg/m³ × 0.008 m × 1.4 m² = 10.2704 kg
The specific heat capacity of ice, c = 2,090 J/(kg·K)
∴ The equation for the heat capacity of the ice to melt, is given as follows;
ΔQ = m·c·ΔT
Where;
ΔT = T₂ - T₁
∴ ΔT = T₂ - T₁ = 273.15 K - 271.15 K = 2 K
ΔQ = 10.2704 kg × 2,090 J/(kg·K) × 2 K = 42.930272 kJ
The latent heat to melt the ice, Q = The latent heat of fusion of ice, L × Mass of ice, m
The latent heat of fusion of ice, L = 334 kJ/kg
∴ Q = 334 kJ/kg × 10.2704 kg = 3,430.3136 kJ
The total heat required to melt the ice, H = ΔQ + Q
∴ H = 42.930272 kJ + 3,430.3136 kJ = 3,473.243872 kJ ≈ 3.473 MJ.
The magnetic coils of a tokamak fusion reactor are in the shape of a toroid having an inner radius of 0.700 m and an outer radius of 1.30 m. The toroid has 900 turns of largediameter wire, each of which carries a current of 14.0 kA. Find the magnitude of the magnetic field inside the toroid along (a) the inner radius and (b) the outer radius.
Answer:
(a) 11.3 T
(b) 6.09 T
Explanation:
Current, I = 14 kA = 14000 A
number of turns, N = 900
inner radius, r = 0.7 m
outer radius, R = 1.3 m
The magnetic field due to a circular coil is given by
[tex]B = \frac{\mu o}{4\pi}\times \frac{2 N\pi I}{R}[/tex]
(a) The magnetic field due to the inner radius is
[tex]B = 10^{-7}\times \frac{2\times 900\times 3.14\times 14000}{0.7}\\\\B = 11.3 T[/tex]
(b) The magnetic field due to the outer radius is
[tex]B = 10^{-7}\times \frac{2\times 900\times 3.14\times 14000}{1.3}\\\\B = 6.09 T[/tex]
Một dây nhôm dài 10 m khi ở 25 độ C. Biết khi nhiệt độ tăng thêm 1 độ C thì chiều dài 1m dây nhôm sẽ tăng thêm 0,024mm.
a) Tính ăng chiều dài của 1m dây nhom khi nhiệt độ tăn thêm 75 độ C
b) Tính chiều dài dây nhôm ở 75 độ C
Answer:
??????? what language is this. um A then
7) A ball is thrown upward at an initial velocity of 8.2 m/s, from a height of 1.8 meters above the ground. The height of the ball h, in metres can be represented, after t seconds, is modelled by the equation h = –4.8t² + 8.2t + 1.8. (a) Determine the height of the ball after 1.7 seconds.
Answer:
8392
Explanation:
d=s/t
The air pressure at the base of the mountain is 75.0cmof mercury while at the top is 60 cm of mercury given that the average density of air is 1.25kg/m³ and the density of mercury is13600kg/m³and g=10N/kg. calculate the height of the mountain?
Answer:
이 질문입니까?
Explanation:
평균 공기 밀도가 1.25kg/m³이고 수은 밀도가 13600kg/m³이고 g=10N/kg인 경우 산 기슭의 기압은 수은의 75.0cm이고 정상의 수은은 60cm입니다. 산의 높이를 계산?
The air pressure at the base of the mountain is 75.0 cm of mercury while at the top is 60 cm of mercury. The height of the mountain is approximately 0.1468 meters.
The pressure difference (∆P) between the base and the top of the mountain is given by:
∆P = ρgh
Where:
ρ is the density of the fluid (mercury) = 13,600 kg/m³
g is the acceleration due to gravity = 10 N/kg
h is the height of the fluid column (mountain)
We have the pressure difference: ∆P = 75.0 - 60.0 = 15.0 cmHg.
To convert cmHg to pascals (Pa), we use the conversion factor: 1 cmHg = 1333.22 Pa.
∆P = 15.0 × 1333.22
∆P = 19,998.3 Pa
h = ∆P ÷ (ρg)
h = 19,998.3 ÷ (13,600 × 10)
h = 0.1468 m
Therefore, the height of the mountain is approximately 0.1468 meters.
To know more about the air pressure:
https://brainly.com/question/15189000
#SPJ5
a car moves at a speed of 40km/h. it is stopped by applying brake which produce a uniform acceleration of-0.5m/s^2. how much distance will it move before coming to stop ? plz its urgent
Answer:
Explanation:
I answered this in question #24313516
Q010) A well in which the water rises on its own to a level above its aquifer Group of answer choices is the result of pressure within a confined aquifer that creates a potentiometric surface. is called an ordinary well. always pushes water higher than the ground surface. cannot be used for commercial or public use, as the water is under too much pressure.
Answer:
The result of pressure within a confined aquifer that creates a potentiometric surface
Explanation:
There are conditions under the Earth's surface, where porous rock layers are tilted and also have a confining, less porous, rock layer about the their boundary, forming a confined aquifer. The existing pressure in the aquifer is therefore confined within the water and the porous rock layer, such that drilling into the pressurized aquifer leads to the water rising under the pressure existing in the aquifer, to a potentiometric surface which is above the actual underground level of the aquifer
A motorcycle starts from rest and gains a velocity of 40m/s in 8 seconds. Find (i) acceleration and (ii) distance travelled by the motorcycle.
• Initial velocity (u) = 0 m/s
• Final velocity (v) = 40 m/s
• time (t) = 8s
Acceleration :[tex]\implies \sf a = \dfrac{\Delta v}{ t} \\ [/tex]
[tex]\implies \sf a = \dfrac{v - u}{ t} [/tex]
[tex]\implies \sf a = \dfrac{40 - 0}{ 8} [/tex]
[tex]\implies \sf a = \dfrac{40}{ 8} [/tex]
[tex]\implies \bf a = 5 \: {ms}^{ - 2} [/tex]
• Distance travelled by the motorcycle:[tex] \longrightarrow \sf {v}^{2} - {u}^{2} = 2as \\ [/tex]
[tex]\longrightarrow \sf {(40)}^{2} - {(0)}^{2} = 2 \times5 \times s \\ [/tex]
[tex] \longrightarrow \sf 1600 = 10s[/tex]
[tex]\longrightarrow \sf s = \dfrac{1600}{10} [/tex]
[tex]\longrightarrow \bf s = 160 \: m[/tex]
Which device is used to measure the weight of a body?
Answer:
The beam balance is a device used for the determination of the mass of a body under gravitation. Beam balance is used for high precision measurements like masses up to 250g, it consists of a pair of scale pans one at each end of a rigid beam.
we use a scale to measure the weight of our bodies
Which of the following changes would not lead to changes in the efficiency of
a heat engine?
A. Doubling the work done while keeping the heat flow into the
engine the same
B. Doubling the heat flow into the engine while halving the work done
C. Doubling both the work done and the heat flow into the engine
D. Doubling the heat flow into the engine while keeping the work
done the same
Explanation:
B. Doubling the heat flow into the engine while halving the work done
hope this helps you
have a nice day
Sort the processes based on the type of energy transfer they involve. condensation freezing deposition sublimation evaporation melting thermal energy added thermal energy removed
Answer:
condensation - thermal energy removed
freezing -thermal energy removed
deposition - thermal energy removed
sublimation - thermal energy added
evaporation - thermal energy added
melting - thermal energy added
Explanation:
Thermal energy is heat energy. Processes in which heat is added involve the addition of thermal energy while processes in which heat energy is removed involves removal of thermal energy.
Condensation involves a change from gas to liquid, freezing involves a change from liquid to solid while deposition involves the settling of mobile particles at a place. All these processes involve a decrease in energy of particles.
On the other hand, sublimation is a direct change from solid to gas, melting involves a change from solid to liquid while evaporation involves a change from liquid to gas. All these processes occur when energy is added to the particles in a system.
Answer:
condensation - thermal energy removed
freezing -thermal energy removed
deposition - thermal energy removed
sublimation - thermal energy added
evaporation - thermal energy added
melting - thermal energy added
If you could travel 900 meters in 55 seconds, what is your speed?
(Answer in details=brainliest)
Answer:
The rate of change of distance is called speed it can also be defined as distance travelled per unit time,from these definition you can tell that the formula will be
speed=distance/time
in this question the distance is 900meters and the time is 55seconds therefore the speed will be:
s=900meters/55seconds
=16.36m/s
I hope this helps
In a lunar experiment, a 950-g aluminum (920 J/(°Ckg)) sphere is dropped from the space probe while is 75 m above the Lunar ground. If the sphere’s temperature increased by 0.11°C when it hits the ground, what percentage of the initial mechanical energy was absorbed as thermal energy by the aluminum sphere?
Answer:
13.759 % of the initial mechanical energy is lost as thermal energy.
Explanation:
By the First Law of Thermodynamics we know that increase in internal energy of the object ([tex]U[/tex]), in joules, is equal to the lost amount of the change in gravitational potential energy ([tex]U_{g}[/tex]), in joules:
[tex]\frac{x}{100} \cdot \Delta U_{g} = \Delta U[/tex] (1)
Where [tex]x[/tex] is the percentage of the energy loss, no unit.
By definition of the gravitational potential energy and internal energy, we expand this equation:
[tex]\frac{x\cdot m \cdot g \cdot h}{100} = m\cdot c\cdot \Delta T[/tex] (1b)
Where:
[tex]m[/tex] - Mass of the object, in kilograms.
[tex]g[/tex] - Gravitational acceleration, in meters per square second.
[tex]h[/tex] - Initial height of the object above the lunar ground, in meters.
[tex]c[/tex] - Specific heat of aluminium, in joules per degree Celsius-kilogram.
[tex]\Delta T[/tex] - Temperature increase due to collision, in degree Celsius.
If we know that [tex]m = 0.95\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]h = 75\,m[/tex], [tex]c = 920\,\frac{J}{kg\cdot ^{\circ}C}[/tex] and [tex]\Delta T = 0.11\,^{\circ}C[/tex], then the percentage of energy loss due to collision is:
[tex]x = \frac{100\cdot c\cdot \Delta T}{g\cdot h}[/tex]
[tex]x = \frac{100\cdot \left(920\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (0.11\,^{\circ}C)}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (75\,m)}[/tex]
[tex]x = 13.759\,\%[/tex]
13.759 % of the initial mechanical energy is lost as thermal energy.
What are three differences and similarities between a Vernier Calipers and a Micrometer? (please leave a good answer)
Answer:
Explanation:
Vernier scale
Mathematical tool
A vernier scale, named after Pierre Vernier, is a visual aid to take an accurate measurement reading between two graduation markings on a linear scale by using mechanical interpolation; thereby increasing resolution and reducing measurement uncertainty by using vernier acuity to reduce human estimation error. Wikipedia
Purpose: Measuring more precisely than could be done unaided when reading a uniformly divided straight or circular measurement scale
Creator: Pierre Vernier
Year invented: 1631
..............................................................................................................................................................................................................................................................................................
A micrometer is a measuring instrument that can make extraordinarily precise measurements. Most micrometers are designed to measure within one one-thousandth of an inch! That's a close fit. Exact measurements like this are necessary when even the smallest of space between objects can cause problems or difficulties.
Micrometer
Mathematical tool
A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for accurate measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers. Wikipedia
Operation supported: Component measurement
Purpose: Precision measurement of a component
Variant: Digital mics, Bench micrometer, Limit mics, Digit mics, MORE
Component: Screw, Spindle, Ratchet stop, Anvil, Frame, Barrel, Thimble lock, Thimble
Application: Mechanical Engineering, Machining
The Weight of an object is more at pole and less at equator of the earth. Give reason
The Weight of an object is more at pole and less at equator of the earth because the distance of the pole is less than the distance of the equator from the centre of the earth.
A boy shoves his stuffed toy zebra down a frictionless chute. It starts at a height of 1.45 m above the bottom of the chute with an initial speed of 1.23 m/s . The toy animal emerges horizontally from the bottom of the chute and continues sliding along a horizontal surface with a coefficient of kinetic friction of 0.231 . How far from the bottom of the chute does the toy zebra come to rest? Assume g=9.81 m/s2 .
Answer:
The answer is "4.97 m".
Explanation:
[tex]u = 1.23\ \frac{m}{s}\\\\[/tex]
[tex]H= 1.45 \ m\\\\[/tex]
[tex]\mu = 0.231\\\\[/tex]
The law of conservation tells us that heat energy at the top with kinetic energy at the top equals kinetic energy at the base.
[tex]mgh+\frac{1}{2}mu^2=\frac{1}{2}mv^2\\\\2gh +u^2 =v^2\\\\v=\sqrt{u^2+2gh}[/tex]
[tex]v=\sqrt{(1.23\ \frac{m}{s})^2+2(9.81 \frac{m}{s^2}) +(1.45\ m)[/tex]
[tex]=\sqrt{1.5129+19.62 +1.45}\\\\=\sqrt{22.5829}\\\\=4.75\ \frac{m}{s}[/tex]
Friction force is given by the formula
[tex]f=-\mu mg \\\\ma= -\mu mg\\\\a=-\mu g\\\\[/tex]
[tex]= -(0.231) \ (9.81\ \frac{m}{s^2})\\\\=-2.26611 \ \frac{m}{s^2}[/tex]
Now by using an equation of motion as
[tex]v^2-u^2= 2as[/tex]
From the above the distance traveled is
[tex]S=\frac{v^2-u^2}{2a}[/tex]
[tex]S=\frac{(0)^2-(4.75\ \frac{m}{s})^2}{2(-2.26611\ \frac{m}{s^2})}\\\\[/tex]
[tex]=\frac{-(4.75\ \frac{m}{s})^2}{2(-2.26611\ \frac{m}{s^2})}\\\\=\frac{-22.5625}{-4.53222}\\\\=4.97[/tex]
In other words, the distance from the bottom of the chute to the point where the toy zebra comes to rest is [tex]s = 4.97\ m[/tex]
Which solution has the greatest number of hydrogen ions?
blood, pH = 7.2
lemon juice, pH = 2
soda, pH = 3.5
bleach, pH = 13.5
Answer:
lemon
Explanation:
the lower the number the hier hydrogen ions
Answer: B
Explanation:
20. A semiconductor is a
A) crystalline solid that conducts current under any condition
B) metallic solid that conducts current under any condition
C) metallic solid that conducts current under certain conditions
D) crystalline solid that conducts current under certain conditions
Answer:
D) crystalline solid that conducts current under certain conditions
Explanation:
A semiconductor is any crystalline solid material whose electrical conductivity is intermediary between that of insulators and conductors. That is, a semiconductor does not conduct like a conductor but does more than an insulator.
Based on this, a semiconductor is said to only conduct electricity under certain conditions as opposed to conductors that do so under any condition. Example of semiconductors are silicon, carbon, antimony, arsenic etc.
A cricket ball of mass 800g has momentum of 20 kg m/sec . Calculate velocity of ball
Answer: 25 m/s
Explanation:
1. rearrange equation p = mv to find v
2. v = p/m - then convert 800 g into kg (= 0.8 kg)
3. plug in p and m - v = 20 / 0.8 = 25 m/s
Answer:
V= 25m/s
Explanation:
Mass=800g
Momentum=20kgm/s
V= ?
Convert 800g to kg
800/1000 = 0.8kg
Momentum=mass× Velocity
Momentum/Mass = Velocity
20/0.8 =25m/s
Who would most likely be required to work with sodium hydroxide?
Answer:
a plumber
Explanation:
