Answer:
a=3.4m because of the m
b=1day because 86400=a day
A water heater marked 4 kW takes 4 minutes to heat 1 kg of water from 20 °C to 50 °C. The cost of electrical energy per kWh
is $0.120. What will be the total cost of energy consumption?
The total cost of the energy consumption for the given time period is $0.0364
The given parameters include;
power rating of the heater, P = 4 kW = 4000 Wtime taken to completely boil the water,[tex]t = 4 \min = 4 \min \times \frac{1 \ h}{60 \ \min} = 0.067 \ h[/tex]mass of the water, m = 1 kginitial temperature of the water, t₁ = 20 ⁰Cfinal temperature of the water, t₂ = 50 ⁰Cspecific heat capacity of water, c = 4200 J/kg⁰Ccost of electrical energy = $0.12The total energy consumed in the process of heating the water;
Total electrical Energy = Energy of the heater (kWh) + Energy of the heated water (kWh)
Energy of the heater (kWh) = power x time
= 4 kW x 0.067 h
= 0.268 kWh
Energy of the heated water (J) = mcΔt
where;
Δt is the change in temperature = t₂ - t₁
= 50 ⁰C - 20 ⁰C = 30⁰C
Energy of the heated water (J) = 1 x 4200 x 30
= 126,000 J
Electrical power of the heated water (Watts) = [tex]\frac{126,000 \ J}{4 \ \min} \times \frac{1 \min}{60 \ s} = 525 \ W[/tex]
Energy of the heated water (kWh) = [tex]\frac{525}{1000} \times 4\min\times \frac{1 \ hr}{60 \min} = 0.035 \ kWh[/tex]
Total electrical Energy = 0.268 kWh + 0.035 kWh
= 0.303 kWh
The total cost of the energy consumed is calculated as;
[tex]Total \ cost = \frac{\$ \ 0.12}{kWh} \times 0.303 \ kWh = \$ \ 0.0364[/tex]
Therefore, the total cost of the energy consumption is $0.0364
To learn more about cost of electrical energy calculation, please visit: https://brainly.com/question/17924004
what is the definition of unit?definition of unit?
Answer:
The Reference standard with which we carry out the measurement of any physical quantity of the same kind is know as unit .
I HOPE I HELP YOU.
Answer:
The standard quantity which is used for the comparison with an unknown quantity is called unit.
Unit is a known or standard quantity in terms of which other physical quantities are measured.
for examples;kilogram,metre,second,etc.
Explanation:
hope it helps you
the hydrometer with the density of liquid to be 800 kg metre per square is the volume of the submerged part of the hydrometer is 5 into 10 to the power minus 5 calculate the mass of the hydrometer
Answer:
Mass = 0.04 Kg
Explanation:
Given the following data;
Density = 800 kg/m³
Volume = 5 * 10^{-5} m³
To find the mass of the object;
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the formula;
[tex] Density = \frac {mass}{volume} [/tex]
Making mass the subject of formula, we have;
[tex] Mass = density * volume [/tex]
Substituting the values into the formula, we have;
[tex] Mass = 800 * 5 * 10^{-5} [/tex]
Mass = 0.04 Kg
The electrical resistance of an element in a platinum resistance thermometer at 100°c, 0°c and room temperature are 75.00Ω, 63.00Ω and 64.992Ω respectively. Use the data to calculate room temperature
Answer:
16.6 °C
Explanation:
From the question given above, the following data were obtained:
Temperature at upper fixed point (Tᵤ) = 100 °C
Resistance at upper fixed point (Rᵤ) = 75 Ω
Temperature at lower fixed point (Tₗ) = 0 °C
Resistance at lower fixed point (Rₗ) = 63.00Ω
Resistance at room temperature (R) = 64.992 Ω
Room temperature (T) =?
T – Tₗ / Tᵤ – Tₗ = R – Rₗ / Rᵤ – Rₗ
T – 0 / 100 – 0 = 64.992 – 63 / 75 – 63
T / 100 = 1.992 / 12
Cross multiply
T × 12 = 100 × 1.992
T × 12 = 199.2
Divide both side by 12
T = 199.2 / 12
T = 16.6 °C
Thus, the room temperature is 16.6 °C
If a roller coaster train has a potential energy of 1,500 J and a kinetic energy of 500 J as it starts to travel downhill, what is its total energy
Its total mechanical energy is 2,000 J.
We don't have enough information to say anything about its heat energy, its chemical energy, or the energy due to any electrical charge it may be carrying or any magnetic field it may have.
please ans both urgent
Answer:
d I guess not sure
b if down I guess
Explanation:
if worng then plz dont say anything as I am not sure about the ans
2- A copper wire of 3mm diameter with conductivity of 6.7 10' (0.M), and electron mobility of 0.0064 m2 /V sec. Is subjected to an electric field of 30 mV/m. Find (a) the charge density of free electrons, (b) the current density, (c) current flowing in the wire, (d) the electron draft velocity.
Answer:
a) [tex]n=5.98*10^{26}/m^3[/tex]
b) [tex]i=2010000A/m^2[/tex]
c) [tex]I_w=14.207A[/tex]
d) [tex]V_e=1.92*10^{-4}m/s[/tex]
Explanation:
From the question we are told that:
Diameter [tex]d=3mm=>3*10^{-3}[/tex]
Conductivity [tex]\sigma= 6.7 10^7 (0.M),[/tex]
Electron mobility [tex]\phi= 0.0064 m2 /V sec[/tex]
Electric field [tex]E= 30 mV/m[/tex]
a)
Generally the equation for Charge Density is mathematically given by
[tex]\phi=\frac{\sigma}{n e}[/tex]
Therefore
[tex]n=\frac{\sigma}{\phi e}[/tex]
[tex]n=\frac{6.7 10^7}{1.6*10^{-19} *0.0064}[/tex]
[tex]n=5.98*10^{26}/m^3[/tex]
b)
Generally the equation for current density is mathematically given by
[tex]i=\sigma*E[/tex]
[tex]i= 30*10^{-3] *6.7 10^7[/tex]
[tex]i=2010000A/m^2[/tex]
c)
Generally the equation for current in wire is mathematically given by
[tex]I_w=iA[/tex]
[tex]I_w=i*\pi r^2[/tex]
[tex]I_w=(2010000)*\pi( 1.5*10^{-3})^2[/tex]
[tex]I_w=14.207A[/tex]
d)
Generally the equation for electron draft velocity. is mathematically given by
[tex]V_e=\phi E[/tex]
[tex]V_e=(0.0064)*(30*10^{-3})[/tex]
[tex]V_e=1.92*10^{-4}m/s[/tex]
What are the units for speed?
O A. km/s2
O B. m/s2
O C. m/s2
O D. m/s
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)
kí hiệu Δs trong vật lí là gì?
Answer:
which language is this
Explanation:
The unit of work in terms of Newton and metre is _______
Answer:
Joule
Explanation:
the unit of work is Joule determined by the letter J.
Answer:
JouleExplanation:
Joule is defined as the work done by a force of one newton causing a displacement of one meter. Sometimes, newton-metre (N-m) is also used for measuring work.
A 750 kg National Geographic Drone is rising vertically up into the atmosphere at constant speed. The lift force pushing it upward is 125% of its weight. The drone reaches the cruising speed almost immediately. It takes 25 seconds for the drone to reach a height of 250m starting from the surface.
a. What is the mechanical energy of the drone at the surface?
b. What is the mechanical energy of the drone at the 150 m height?
c. Is the mechanical energy of the drone conserved, increased, or decreased. Explain your choice.
d. What is the work done by each force acting on the drone?
Answer:
a. 0
b. 1.103625 MJ
c. Conserved
d. 1.103625/n MJ where n = The number of forces
Explanation:
The mass of the drone, m = 750 kg
The upward lift force = 125% of the weight of the drone
The time it takes the drone to reach a height of 250 m = 25 seconds
a. The mechanical energy = The kinetic energy + Potential energy
Therefore, given that the drone stars motion from the surface and was initially at rest, the mechanical energy at the surface = 0
b. The mechanical energy at height, h = 150 m, ME₁₅₀ = The potential energy gained = m·g·h
Where;
g = The acceleration due to gravity = 9.81 m/s²
∴ ME₁₅₀ = 750 kg × 9.81 m/s² × 150 m = 1103625 J = 1.103625 MJ
c. The mechanical energy is equivalent to the potential energy of the drone at the 150 m height, therefore, it is conserved
d. The work done by the force = The energy gained
Therefore, where there are n number of forces, the work done by each force = 1.103625/n MJ
A long distance runner running a 5.0km track is pacing himself by running 4.5km at 9.0km/h and the rest at 12.5km/h. What is his average speed?
Answer:
9.26 km/h
Explanation:
Applying,
V' = D'/t'............... Equation 1
Where V' = Average speed, D' = Total distance, t' = total time.
Given: D' = 5 km
But,
v = d/t............ Equation 2
Where v = speed , d = distance, t = time
t = d/v............ Equation 3
Given: d = 4.5 km, v = 9 km/h, and d = 0.5 km, v = 12.5 km/h
Therefore,
t₁ = 4.5/9 = 0.5 hours
t₂ = 0.5/12.5
t₂ = 0.04 hours
Therefore,
V' = 5/(0.5+0.04)
V' = 5/0.54
V' = 9.26 km/h
For Gerald the Human Cannonball, the gunpowder transforms and gives Gerald what type of energy?
Explanation:
The explosives changes Gerald the Human Cannonball and provides him with chemical energy.
Sulfur and carbon serve as fuels, whereas saltpetre serves as an oxidant. Gunpowder has long been employed as a propellant in weapons, artillery, rocketry, and fireworks, as well as a blasting ingredient in quarrying, mine, and road construction.
Câu 1. Con lắc lò xo treo thẳng đứng, dao động điều hòa với biên độ 2cm và tần số góc 20 rad/s. Chiều dài tự nhiên của lò xo là 30cm. Chiều dài nhỏ nhất và lớn nhất của lò xo trong quá trình dao động là bao nhiêu? Lấy g = 10m/s2.
Answer:
28 cm and 32 cm
Explanation:
1. The spring pendulum hangs vertically, oscillates harmonic with amplitude 2cm and angular frequency 20 rad/s. The natural length of
a spring is 30cm. What is the minimum and maximum length of the spring during the oscillation? Take g = 10m/s2.
As the amplitude is 2 cm and the natural length is 30 cm. So, it oscillates between 30 -2 = 28 cm to 30 + 2 = 32 cm.
So, the minimum length is 28 cm and the maximum length is 32 cm.
A skipper on a boat notices wave crests passing his anchor chain every 5.6 s . He estimates the distance between wave crests to be 16 m . He also correctly estimates the speed of the waves. Find this speed.
Answer:
v = 2.85 m/s
Explanation:
Given that,
A skipper on a boat notices wave crests passing his anchor chain every 5.6 s.
The distance between wave crests to be 16 m.
We need to find the speed of the waves. The speed of a wave can be calculated by the formula as follows :
[tex]v=f\lambda\\\\v=\dfrac{\lambda}{T}\\\\v=\dfrac{16}{5.6}\\\\v=2.85\ m/s[/tex]
So, the speed of the wave is 2.85 m/s.
1. What type of VOM reading requires the meter to be placed in series with the circuit?
A. Resistance
B. Voltage
C. Current
O
D. Power
Answer:
C. Current.
Explanation:
In a series circuit the current is equal in all of its components, so to measure the current we put the meter in series with the circuit.
Define electric current and drift velocity.
Answer:
Current- the flow of free charges, such as electrons and ions
Drift velocity- the average speed at which these charges move
Answer:
An electric current is the stream of changed particals, such as electrons & ions, moving through an electrical conductor.
The average velocity attained bycharged partical ,such as electrons,in a material due to electric fields
If we aim a radio telescope at a distant spiral arm of the Milky Way Galaxy, we will probably observe a 21-cm line. If we point a large optical telescope at this same region, we will probably not be able to detect the neutral hydrogen that gives rise to the 21-cm radio signal. Why not
Answer:
Because of the interstellar dust and interior location of the solar system.
Explanation:
We will probably not be able to detect the neutral hydrogen that gives rise to the 21-cm radio signal if we point a large optical telescope to the region because, the interstellar dust obscures the location of the spiral arm of the Milky way galaxy and this makes neutral hydrogen that gives rise to the 21-cm radio signal difficult to detect.
Also, the interior location of the solar system also makes the neutral hydrogen that gives rise to the 21-cm radio signal difficult to detect.
So, the interstellar dust and the interior location of the solar system makes it difficult to detect the neutral hydrogen that gives rise to the 21-cm radio signal with a large optical telescope.
A ball that has a mechanical energy of 65 J has 12 J of kinetic energy. The ball has
J of potential energy
Answer:
The ball has a potential energy of 53 J.
Explanation:
Mechanical energy, E = Kinetic energy + Potential energy
E = K.E + P.E
65 = 12 + P.E
P.E = 65 – 12
P.E = 53 J
Therefore the potential energy of the ball is 53 J
Answer:
53
Explanation:
on e2021
Una rueda tiene 4 cm de diámetro y realiza
200 vueltas cada 5 minutos. Calcular:
a. la frecuencia
b. el período
c. la velocidad lineal o tangencial
d. La velocidad angular
e. La aceleración centrípeta.
Answer:
Una rueda tiene 4 cm de diametro y realiza 200 vueltas cada 4 minutos calcular a frecuencia b el periodo c la velocidad lineal l tangencial
A train travels 600 kilometers in 1 hour. What is the train's velocity in meters/second?
here's the answer to your question
The density of a material in CGS system of units is 4g cm-³. In a system of units in which unit of length is 10 cm and unit of mass is 100g, the value of density of material will be...?
1) 0.04
2) 40
3) 0.4
4) 400
[tex]\sf\underline{Solution:}[/tex]
Here , the density of the material is 4g cm³ but it is not given in CGS system.
$\sf{As\:we\:know\:that:}$
$\sf\bold{Density=}$ $\sf\dfrac{Mass}{Volume}$
$\space$
[tex]\sf{Now,according \: to \:the\:question:}[/tex]
$\sf\small{Density\:of\:the\:material=4}$ $\sf\dfrac{g}{cm^2}$
$\space$
$\sf{It\:is\:given\:that:}$
In the system of units the mass is 100gram.
$\space$
Hence,
$\sf{The\:mass\:unit\:for\:4g=}$ $\sf\dfrac{4}{100}$ $\sf{units}$
$\space$
In the system of units,the length is 10cm.
Henceforth,
$\sf\small{The\:length \:for\:1cm\:units=}$ $\sf\dfrac{1}{10}$ $\sf{units}$
$\space$
☆ Substitute the required values in the given formula-
$\sf\purple{Density=}$ $\sf\dfrac\purple{Mass}\purple{volume}$
$\space$
$\sf\underline\bold{Density\:of\:the\:material:}$
= $\sf\dfrac{4/100}{1/10^3}$ $\sf\bold{units}$
$\space$
= $\sf\dfrac{4/100}{1/1000}$ $\sf\bold{units}$
$\space$
= $\sf\dfrac{4000}{100}$ $\sf\bold{units}$
$\space$
$\sf\underline\bold\blue{=40\:units}$
$\sf\small{Therefore,option\:2nd\:is\:correct!}$
_______________________________
A plane mirror produces a _____.
virtual image
refracted image
real image
Answer:
Explanation:
A plane mirror is the kind you look into when you look into a "regular" mirror. The image you see is right-side-up. These images are virtual. Real images are always upside down and are made by mirrors that are "parabolic" in shape. Virtual images are always right-side-up.
J.J. Thomson theorized that, if an atom had all of its negatively charged
electrons removed, the remaining material would be
A. neutral
B. negatively charged
C. positively charged
D. magnetic
Answer:
C. Positively charged
Explanation:
The plum pudding model of the atom proposes by J. J. Thomson consisted of electrons which lay embedded as the raisins within a dough or soup that was positively charged. The electron was discovered by J. J. Thomson in 1897 through cathode ray tube experiments.
Based on the plum pudding model, if all the negatively charge electrons contained in an atom are removed, the material remaining will be the positively charged soup
Use the KMT to explain what happens to water vapor when it encounters a
cold glass of water.
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 court would you go to if you wanted to declare bankruptcy?
A.
Civil court
B.
U.S. Court of Appeals
C.
Supreme Court
D.
U.S. District Court
Answer:
A. Cilvil court.........
Civil court would you go to if you wanted to declare bankruptcy. The correct option is A.
Thus, According to the United States Bankruptcy Code, bankruptcy proceedings are typically filed in a federal bankruptcy court.
The federal court system includes these courts, which deal with Chapter 7, Chapter 11, and Chapter 13 bankruptcy cases.
The additional alternatives (U.S. Court of Appeals, Supreme Court, and U.S. District Court) are not the main courts where bankruptcy cases are generally filed.
Thus, Civil court would you go to if you wanted to declare bankruptcy. The correct option is A.
Learn more about Civil court, refer to the link:
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how is speed different from velocity
Answer:
Speed is a time for how long an object is moving
Velocity is the direction of an object
An engineer wants to design an oval racetrack such that 3.20×103 lb racecars can round the exactly 1000 ft radius turns at 99 mi/h without the aid of friction. She estimates that the cars will round the turns at a maximum of 175 mi/h. Find the banking angle θ necessary for the race cars to navigate the turns at 99 mi/h without the aid of friction.
Answer:
the angle of banking is 33.3 degree.
Explanation:
speed, v = 99 mi/h = 44.26 m/s
radius, r = 1000 ft = 304.8 m
g = 9.8 m/s^2
Let the angle of banking is A.
[tex]tan A = \frac{v ^2}{r g}\\\\tan A = \frac{44.26^2}{304.8\times 9.8}\\\\tan A = 0.66\\\\A = 33.3^0[/tex]
An iron weight, suspended by a string, is motionless. The tension
in the string is 4.75 newtons. What is the mass of the iron
weight?
Answer:
Explanation:
If the mass hangs at the end of the string and the string can support the mass and doesn't break, and the mass hangs still, that means that the tension in the string is equal to the downward pull of the mass. However, we are given the tension in Newtons and the mass needs to be in kg. So we use the equation for weight:
w = mg where w, the weight, is the same as the tension in the string. Gravity is always 9.8 in the metric system:
4.75 = m(9.8) so
m = .48 kg
Answer:
Answer: A
0.485 Kg
Explanation:
how far away is a train if you see the steam from is nozzle 4.5 seconds
before you hear its sound?(take speed of sound as 331 m/sec)
Answer:
Distance = 1489.5 meters
Explanation:
Given the following data;
Time = 4.5 secondsSpeed of sound = 331 m/sTo find how far away is the train;
Mathematically, the distance of an object is calculated using the formula;
Distance = speed * time
Distance = 331 * 4.5
Distance = 1489.5 meters
