Is velocity ratio of a machine affected by applying oil on it?Explain with reason.
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.
Name the type of relationship between current and potential difference for a resistor at constant temperature. [
The current flowing through a resistor at a constant temperature is directly proportional to the potential difference across it. This is called Ohm's law
Lúc 7g bạn an đi từ nhà đến trường với tóc độ trung bình là 20km/h . Bạn đến trường lúc 7g20. Tính khoảng cách từ nhà tới trường?
Answer:
Distance = 6.667 kilometres
Explanation:
Given the following data;
Speed = 20 km/h
Departure time = 7:00
Arrival time = 7:20
Time taken = 20 minutes
To calculate the distance travelled from home to school;
First of all, we would have to convert the value of time in minutes to hours.
Conversion:
60 minutes = 1 hour
20 minutes = X hours
Cross-multiplying, we have;
X = 20/60 = 1/3 hours
Mathematically, the distance travelled by an object is calculated by using the formula;
Distance = speed * time
Distance = 20 * 1/3
Distance = 20/3 =
Distance = 6.667 kilometres
Muốn đun sôi 200g nước từ 30 độ cần cung cấp nhiệt lượng bao nhiêu :
Answer:
cần cung cấp 70 độ vì nước sôi ở 100°C
Explanation:
Question 7 of 25
Which two chemical equations are balanced?
O A. 2PBrg + 3Cl2 - 2PC13 + 3Br2
O B. 2Na+ MgCl2
2NaCl + Mg
-
C. 2LIOH + 2H2S - Li2S + 2H20
D. 2AgNO3 + NaCl - NaNO3 + 2AGCI
Answer:
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
2Na + MgCl₂ → 2NaCl + Mg
Explanation:
A balanced chemical equation is a chemical equation that have an equal number of elements of each type on both sides of the equation
Among the given chemical reactions, we have;
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
In the above reaction;
The number of phosphorus, P, on either side of the equation = 2
The number of bromine atoms, Br, on either side of the equation = 6
The number of chlorine atoms, Cl, on either side of the equation = 6
Therefore, the number of elements in the reactant side and products side of the reaction are equal and the reaction is balanced
The second balanced chemical reaction is 2Na + MgCl₂ → 2NaCl + Mg
In the above reaction, there are two sodium atoms, Na, one magnesium atom and two chlorine atoms on both sides of the reaction, therefore, the reaction is balanced
a bus starts to move from rest if its velocity becomes 90 km per hour after 8 speed calculate its acceleration.
write with full process.
answer=3.13ms–²
Answer:
Acceleration, a = 3.13 m/s²
Explanation:
Given the following data;
Initial velocity = 0 m/s (since it's starting from rest).
Final velocity = 90 km/h
Time = 8 seconds
Conversion:
90 km/h = (90 * 1000)/3600 = 25 m/s
To find the acceleration, we would use the first equation of motion;
V = U + at
Where;
V is the final velocity.
U is the initial velocity.
a is the acceleration.
t is the time measured in seconds.
Substituting into the equation, we have;
25 = 0 + a*8
25 = 8a
Acceleration, a = 25/8
Acceleration, a = 3.125 ≈ 3.13 m/s²
An object is thrown with velocity 7.1 m s-1 vertically upwards on the Moon. The
acceleration due to gravity on the Moon is 1.62 ms? What is the time taken for the object to return to its starting point?
A 3.5 s
B 4.4 s
C 6.5 s
D 8.8 s
Answer:D
Explanation:
Question in the picture please help me...
Show all steps please....
Answer: i)A to B : (ice) freezing
ii) B to C (water) boiling
C to D (steam) evaporating
explanation: 0° is the freezing point of water when temperature increases from 0° the water starts melting. As 100° is the boiling point of water so at 100° the water completely melts and it starts boiling during boiling water changes into steam(water vapour) and it evaporates
how does she hold a newspaper while reading without using the lens? why?
Convert 1nanosecond in to its SI init
Convert 1nanosecond in to its SI init
In SI units, nano is 1000th part of micro which in turn is 1000th part of mini which in turn is 1000th part of main unit. Now, when you affix nano to any unit, here in case, second, it means that you are referring to 1000th part of 1000th part of 1000th part of second or in short, 1000000000th(10^9) part of a second.
In SI units, nano is 1000th part of micro which in turn is 1000th part of mini which in turn is 1000th part of main unit. Now, when you affix nano to any unit, here in case, second, it means that you are referring to 1000th part of 1000th part of 1000th part of second or in short, 1000000000th(10^9) part of a second.So to convert nanosecond into second, just multiply the nanosecond with 0.000000001 or (10^-9)
Help quick
How does the ramp produce mechanical advantage?
A it reduces the amount of input force needed to do a certain amount of work
B it reduces the distance over which the input force needs to be applied
C it reduces the amount of useful work done on objects move it up the ramp
D what is the overall amount of work done on object moving up the ram
C it reduces the amount of useful work done on objects move it up the ramp
What acceleration is produced on a mass of 200g, when a force of 10N is exerted on it?
Answer:
f=ma......10N=0.2a....=50m/s
Answer:
here,
force = mass× acceleration
10 = 0.2 kg × a
or, 10/0.2=a
or, a = 50km/h^2
is the required ans .
a. What is the physical quantity in which force is divided by area called?
Any guess 50 pts + brainlist if correct
Answer:
pressure
Explanation: pressure=force/area
Answer:
The quantities that can be measured are called physical quantities.....
Make a tree diagram based on the topic motion which includes all the concept like uniform & non uniform motion accelerated motion equation of motion motion etc
I think it is a education tips
What is the purpose of the lab the importance of the topic and the question you are trying to answer?
perpose of lab is to store apparatus and do some experiment
Helps someone to know the exert lengh of something
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
A tennis player hits a ball hard and 0.80 seconds later hears the echo from a wall. The speed of sound in air is 340m/s how far away is the player from the wall
Answer:
136 m.
Explanation:
From the question given above, the following data were obtained:
Time (t) = 0.80 s
Speed of sound (v) = 340 m/s
Distance (x) =?
The distance of the player from the wall can be obtained as follow:
v = 2x / t
340 = 2x / 0.80
Cross multiply
2x = 340 × 0.80
2x = 272
Divide both side by 2
x = 272 / 2
x = 136 m
Thus, the distance of the player from the wall is 136 m
1. Imagine a bowling ball with a mass of 5,0 kg that is dropped from a height of 100m,
a. At the moment the bowling ball is dropped it is at a height of 100m, What is its
potential energy?
b. At the moment the bowling ball is dropped, it is not yet moving. Therefore, its
kinetic energy is what?
c. What is the total of both potential and kinetic energy?
a.
Given,
height (h) = 100m
mass (m) = 5kg
acceleration due to gravitation (g) = 9.8ms^-2
Potential energy
= mgh
= 5kg × 9.8ms^-1 × 100m
= 4900 kgm²s^-2
= 4900 J
b.
Since the ball is not moving yet, its kinetic energy is 0.
c.
The total of potential and kinetic energy at every point of the journey is same, i.e., 4900 J.
1) The position of an object to the north of a flagpole is given by x(t) = bt2 – c , where b and c are constants.
a) What is v(t), the velocity of the object as a function of time?
b) What is a(t), the acceleration of the object as a function of time?
c) At some time t the object is located at the flagpole. What is the velocity of the
object at that instant?
Answer:
a) The velocity of the object as a function of time, v(t) is 2·b·t
b) The acceleration of the function of time, a(t) is 2·b
c) The time at which the object is at the flagpole is t = √(c/b)
Explanation:
The function that gives the position of the object north of the flagpole, x(t) is presented as follows;
x(t) = b·t² - c (b and c are constants)
a) The velocity of the object as a function of time, v(t), is derived as follows
v(t) = x'(t) = d(b·t² - c)/dt = 2·b·t
The velocity of the object as a function of time, v(t) = 2·b·t
b) The acceleration of the function of time, a(t) = v'(t) = d(2·b·t)/dt = 2·b
c) The time at which the object is at the flagpole is given by the x-intercept of the function, where x(t) = 0, as follows;
At the x-intercept, we have, x(t) = 0 and x(t) = b·t² - c
∴ 0 = b·t² - c, which gives
b·t² = c
t² = c/b
t = ±√(c/b), we reject the negative value to get;
The time at which the object is at the flagpole, t = √(c/b).
A 250–g piece of gold is at 19 °C. 5.192 kJ of energy is added to it by heat. The specific heat of gold is 129 J/(kg·°C). Calculate its final temperature.
We heat a 25–g sample of metal from 10 °C to 100 °C. 1.082 kJ of energy is added to it by heat. Calculate
the specific heat of the metal.
Answer:
A. DT is given by Q= MCs DT
m = mass of the substances
Cs= is it's specific heat capacity
Ck= Q
Mk ×DTk
=250 × 9 × 5
129
=Dt = 180.1085271
answer is 180degree C.
Explanation:
B. = 25×10 ×100
1.082
=2500
1.082
= 23105.360 g/kj.
The final temperature is 180 degree. and the specific heat of the metal is 23105.360 g/kj.
How to calculate the specific heat?Q = m . C . ΔT
Q = heat; m = mass; C is the specific heat and
ΔT = Final T° - Initial T°
Q = C lat . m
Q = Heat
m = mass
C lar = Latent heat of fusion
A) DT is given by Q= M Cs DT
where, m = mass of the substances
Cs= is it's specific heat capacity
Ck= Q
Mk × DTk
=250 × 9 × 5
129 =Dt = 180.1085271
Thus, the final temperature is 180 degree.
B) We heat a 25–g sample of metal from 10 °C to 100 °C. 1.082 kJ of energy is added to it by heat = 25×10 ×100
=2500
1.082
Q = 23105.360 g/kj
Hence, the specific heat of the metal is 23105.360 g/kj.
Learn more about heat here;
https://brainly.com/question/12909121
#SPJ2
A person has power of 550 watt. What does it mean?
Answer:
It means that person can do work or can posses energy at a rate of 550 watts.
Or : can posses energy of 550 joules in one second.
Explanation:
[tex]{ \bf{power = \frac{work}{time} }}[/tex]
Ра:
5. Mass of the earth is 6x10-kg and its radius is 6400km. What is the
mass of a man weighting 977N?
(99.99kg)
ma
Orth
be
Answer:
what do u need help with
Explanation:
Pа: 5. Mass of the earth is 6x10-kg and its radius is 6400km. What is the mass of a man weighting 977N? (99.99kg) ma. Orth be.
Think of a body which is at rest but not in equilibrium
Answer:
I think the sun is the right answer
PLS PLS PLS HELP ME! IT IS DUE IN TEN MINUTES
For his next stunt, Super Dave (80 kg) starts running at 2.00 m/s, then slides down a frictionless slide which is elevated 12.0 m above the ground, then slides across the rough asphalt ground to slow him to a stop (ouch!) He slides across the asphalt for 8.00 m before coming to a stop. What is the coefficient of friction between Super Dave and the ground?
Answer:
Preface to Students: Welcome to Physics! iv. 1 Motion. 1. 1-1 Speed, Velocity, and. Acceleration. 1. 1-2 Free Fall. 8. 2 Vectors and Projectiles.
257 pages·3 MB
Explanation: I hope this helpssss!!!
28 Why is soft iron used for the core of an electromagnet?
А Soft iron easily becomes a permanent magnet.
B Soft iron is a good electrical conductor.
с Soft iron is a poor thermal conductor.
D Soft iron loses its magnetism when the current in the coil is switched off.
Answer:
An electromagnet is a form of magnet that is made by the passage of electric current through a coil of wire. The core of an electromagnet increases the strength of the produced magnetic field
Soft iron is used as the core of an electromagnet because soft iron is a magnetic material and therefore it is permeable to and becomes magnetized by the magnetic field coming from the flowing current, thereby allowing more flux to pass through the core of the electromagnet, producing a magnetic field strength that is several times that of an air core electromagnet as the relative permeability (to magnetic flux, compared to vacuum) of soft iron is about 64 × 10³
However, once the current is switched, the soft iron does not remain its magnetic, and therefore, the electromagnet becomes demagnetized, thereby being able to maintain its electromagnetic characteristics (being made magnetic by the flow of electric current)
Explanation:
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
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 .
how can we maintain peace in the nature and surrounding
Answer:
6 Ways To Promote Peace
Treat all people with kindness, regardless of race, gender orientation, sexual orientation, religion, etc.
Attend a peace rally.
Write to your government (local and federal)
Create a peaceful affirmation/mantra.
Don't engage in violence of any kind.
Don't purchase weapons.
A golf club hits a 0.04551 kg golf ball off a golf tee. The club is in contact with the ball for 0.020 s, and the force applied by the club is 115 N. What is the speed of the ball as it leaves the tee
Answer:
v = 50.5 m/s
Explanation:
F = (m)(^v/^t)
115N = (0.04551kg)(v/(0.020s))
2,526.917161 m/s² = v/(0.020s)
v = 50.53834322 m/s
v = 50.5 m/s
Will mark brainlest helpp!!!!!!
Answer:
I don't know if it is correct or not.
Convert to m/s
[tex]\\ \Large\sf\longmapsto v=60\times \dfrac{5}{18}=16.6m/s[/tex]
Time=t=5min=5×60=300sWe know
[tex]\boxed{\Large{\sf Acceleration=\dfrac{v-u}{t}}}[/tex]
[tex]\\ \Large\sf\longmapsto Acceleration=\dfrac{16.6-0}{300}[/tex]
[tex]\\ \Large\sf\longmapsto Acceleration=\dfrac{16.6}{300}[/tex]
[tex]\\ \Large\sf\longmapsto Acceleration=0.05m/s^2[/tex]
Distance=sUsing second equation of kinematics
[tex]\boxed{\Large{\sf s=ut+\dfrac{1}{2}at^2}}[/tex]
[tex]\\ \Large\sf\longmapsto s=0(300)+\dfrac{1}{2}(0.05)(300)^2[/tex]
[tex]\\ \Large\sf\longmapsto s=0.05\times 150^2[/tex]
[tex]\\ \Large\sf\longmapsto s=0.05\times 22500[/tex]
[tex]\\ \Large\sf\longmapsto s=1125m[/tex]
