Answer:
3.24×10⁸ J, or 324 MJ
Explanation:
"kWh" is a kilowatt-hour. It's the energy used by 1 kilowatt of power after one hour.
A kilowatt is a kilojoule per second.
90 kWh
= 90 kW × 1 hr
= 90 kJ/s × 1 hr
= 90 kJ/s × 3600 s
= 324,000 kJ
= 324,000,000 J
The energy is 3.24×10⁸ J, or 324 megajoules.
How can you define a solution to an equation?
in the derivation of the time period of a pendulum in electric field when considering the fbd of bob to find the g effective why do we neglect tension
Answer:
we learned that an object that is vibrating is acted upon by a restoring force. The restoring force causes the vibrating object to slow down as it moves away from the equilibrium position and to speed up as it approaches the equilibrium position. It is this restoring force that is responsible for the vibration. So what forces act upon a pendulum bob? And what is the restoring force for a pendulum? There are two dominant forces acting upon a pendulum bob at all times during the course of its motion. There is the force of gravity that acts downward upon the bob. It results from the Earth's mass attracting the mass of the bob. And there is a tension force acting upward and towards the pivot point of the pendulum. The tension force results from the string pulling upon the bob of the pendulum. In our discussion, we will ignore the influence of air resistance - a third force that always opposes the motion of the bob as it swings to and fro. The air resistance force is relatively weak compared to the two dominant forces.
The gravity force is highly predictable; it is always in the same direction (down) and always of the same magnitude - mass*9.8 N/kg. The tension force is considerably less predictable. Both its direction and its magnitude change as the bob swings to and fro. The direction of the tension force is always towards the pivot point. So as the bob swings to the left of its equilibrium position, the tension force is at an angle - directed upwards and to the right. And as the bob swings to the right of its equilibrium position, the tension is directed upwards and to the left. The diagram below depicts the direction of these two forces at five different positions over the course of the pendulum's path.
that's what I know so far
1. Si tengo medio kilo de fruta y te doy un cuarto y tú me das tres cuartos de kilo, ¿cuánto tengo? 2. Si en una carrera te queda por recorrer la mitad de la mitad de 1 km, ¿cuánto te falta? 3. ¿Qué pesa mas, un kilo y medio de hierro o tres medios kilos de paja? porfavor es urgente.
Answer:
1. Tienes 1 kg de fruta.
2. Queda por recorrer 1/4 km.
3. Ambos pesan lo mismo.
Explanation:
1. Tienes 1/2 kg y cuando te doy 1/4 te queda:
[tex] m = \frac{1}{2} - \frac{1}{4} = \frac{1}{4} [/tex]
Ahora cuando te doy 3/4 kg te queda en total:
[tex] m_{T} = \frac{1}{4} + \frac{3}{4} = 1 kg [/tex]
Por lo tanto, tienes 1 kg de fruta al final.
2. Si falta por recorrer la mitad de la mitad, tenemos:
[tex] d = \frac{1/2}{2} = \frac{1}{4} [/tex]
Entonces, queda por recorrer 1/4 km.
3. El peso (P) del hierro es:
[tex] P = m*g [/tex]
[tex] P = (1 + 1/2)kg*9.81 m/s^{2} = 14.72 N [/tex]
Y el peso de la paja es:
[tex] P = 3/2 kg*9.81 m/s^{2} = 14.72 N [/tex]
Por lo tanto, ambos pesan lo mismo.
Espero que te sea de utilidad!
Find the odd one out a)Planets moving on it's axis,Strings of guitar (being played),Motion of a ferry wheel,The vehicles moving on a straight road. b)Motion of the moon around the earth,Motion of the earth around the sun,Motion of a merry-go-round,Heart-beat in a healthy person. c)Motion of a bullet fired from gun,Motion of a football player in the ground,Motion of a vehicle on a straight road,Motion of an apple falling from a tree
Answer:
a) Strings of guitar (being played)
b) Heart-beat in a healthy person
c) Motion of an apple falling from a tree
Explanation:
a) The motion of the string of a guitar being played is the only motion involving simple harmonic motion.
b) All the other motions are circular motion except the heart beat in a healthy person, which is periodic.
c) The motion of an apply falling from a tree is the only motion under the complete influence of gravity from the onset till the end.
Question 5
Calculate the kinetic energy of a car (m - 800 kg) moving at 15 m/s. Write your answer to the nearest whole number in the blank space
provided. Only write the numerical value of the answer without units. Do not leave any space in between numbers.
Answer: Joules
Answer:
90,000Explanation:
[tex]m =800kg\\v = 15\\\\K.E = \frac{1}{2}mv^2\\ K.E= \frac{1}{2} \times 800\times 15^2\\= 400 \times 225\\= 90000 joules\\= 90 kilojoules[/tex]
Calculate the volume of this regular solid. A cylinder labeled B at the top, 13 centimeters high with a radius of 4 centimeters. What is the volume of the cylinder? Round your answer to the nearest hundredth.
Answer:
The volume of the cylinder is [tex]653.71\ \text{cm}^3[/tex]
Explanation:
Given that,
The height of the cylinder is 13 cm
Radius of the cylinder is 4 cm
We need to find the volume of the cylinder. The formula that is used to find the volume of a cylinder is given by :
[tex]V=\pi r^2 h\\\\V=\dfrac{22}{7} \times (4)^2 \times 13\\\\V=653.71\ \text{cm}^3[/tex]
So, the volume of the cylinder is [tex]653.71\ \text{cm}^3[/tex]
Answer:
653.45 is the answer
Explanation:
the resistance per meter is 10 ohm. if the resistance of the material of the wire is 50 then 10^-8 ohm. find the area of cross section of the wire.
the question is at some point wrong or missing a word please help me with the question and answer!
Answer:
5×10⁻⁸ m²
Explanation:
I assume you mean the resistivity of the material is 50×10⁻⁸ Ωm.
R = ρL/A
10 Ω = (50×10⁻⁸ Ωm) (1 m) / A
A = 5×10⁻⁸ m²
Comic-strip hero Superman meets an asteroid in outer space and hurls it at 800 m/s, as fast as a bullet. The asteroid is a thousand times more massive than Superman. In the strip, Superman is seen at rest after the throw. Taking physics into account, what would be his recoil speed (in km/s)?
Answer:
800km/s
Explanation:
Initial momentum = final momentum
the total momentum is zero, Before the release of the asteroid , but Superman and the asteroid are not moving.
So, according to the Conservation of momentum the total momentum when the astronaut is been thrown will equals to zero . Then we can say
Initial momentum = final momentum
Because the momentum of the Superman immediately the asteroid is been thrown is equal to the momentum of the asteroid
Momentum =(mass ×velocity)
the mass of the asteroid i= 1000M
Given velocity = 800 m/s,
momentum =(1000M)(800 m/s)
= 800,000M m/s.
to get the answer, we need to divide by Superman's mass, M, which gives his recoil velocity of 800,000 m/s.
But we're told to convert to km/ s
We know that 1m/s=0.001km/s
=(800,000M m/s)× (0.001km/s)
=800km/s
Therefore, his recoil speed (in km/s) is 800km/s
Which statement best describes semi-conductors? Lack free electrons that can move to other atoms Electrons within their atoms are strongly held by the nuclei Most electrons within their atoms are paired Electricity can flow through it under special conditions
Answer:
Option D (Electricity can flow through it under special conditions ) seems to be the correct choice.
Explanation:
A semiconductor has become a crystal substance with improved electrochemical properties although the temperature is increased. That would be to say, it often functions as an insulating material rather than as a conductor or a circuit. Chemical solvents could perhaps greatly enhance its conducting capacity.Other options that are provided are not related to the given theory. So that the above would be the correct choice.
Statement "Lack free electrons that can move to other atoms " describe semi-conductor.
Properties of Semiconductor:A semiconductor is a type of crystalline solid that is halfway between a conductor and an insulator in terms of electrical conductivity. A semiconductor is conducting in nature because it has free electrons and holes.So that, Lack free electrons that can move to other atoms.Learn more about the Semiconductor here:
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In no more than five simple statements, use the kinetic theory to explain why an iron bar expands when it is heated.
Answer:
Iron expands because heating increases the space between the molecules
Explanation:
According to the kinetic molecular theory, all matter is composed of atoms and molecules which are in constant motion.
When a substance is heated, molecules of the substance begin to vibrate faster. This faster vibration leads to increased space between the molecules (expansion) . The kind of motion motion and degree of spacing of the molecules determine the state of matter in which the substance is found.
Hence, when an iron bar is heated, it expands due to increased motion of its molecules leading to spaces between them.
select the correct relationship of the densities of the given substances: !●water < iron < aluminium < mercury ● Iron < water < mercury < aluminium ● water < aluminium < iron < mercury ● none of the above. asap plz!!!
Answer:
option a is correct
Explanation:
water ∠iron∠aluminium∠mercury
water density =1.0000
iron =7.487
aluminium=2.07
mercury=13.59
Will mark as BRAINLIEST.......
The position vector is given by vector r= 5t² I cap + 2 t³ j cap + 2 k cap. Find it's velocity and acceleration at t=2s.
Answer:
We have the position vector given in terms of time t. r(t) = t^3*i + t^2*j
To find the velocity vector we have to differentiate r(t) with respect to time.
r'(t) = 3t^2*i + 2t*j
The vector representing acceleration is the derivative of the position vector
r''(t) = 6t*i + 2*j
When time t = 2.
The velocity vector is 3*2^2*i + 2*2*j
=> 12*i + 4*j
The speed is the absolute value of the velocity vector or sqrt(12^2 + 4^2) = sqrt (144 + 16) = sqrt 160
The acceleration vector is 6*2*i + 2*j
=> 12*i + 2*j
The required acceleration at t=2 is 12*i + 2*j and the speed is sqrt 160.
Explanation:
Can I have thx and brainliest?
*If someone says v-u=0 ,what does it mean. *What is the relation among mometum,mass and velocity. *A moving bus a little distance forward even when breaks are applied on it which Newton's laws work here? *Under what conditions acceleration of a moving object will be zero?
Answer:
1) It means that the acceleration is 0
2) Momentum, p = Mass, m × Velocity, v
3) Newton's second law of motion
4) The conditions where there are no resultant forces acting on the object
Explanation:
1) The value v - u = 0 means that the acceleration is 0
The relation between v and u is v = u + a·t
v - u = a·t
When v - u = 0 we have;
a·t = 0
a = 0 or t = 0
Acceleration, a = 0
2) The relation between momentum, mass and velocity is
Momentum, p = Mass, m × Velocity, v
p = m × v
3) The bus moving a little distance forward even when the breaks are applied is due to the following relation;
Force = Rate of change of momentum produced
Which is Newton's second law of motion
Therefore, where the the force is low, the rate of change of the momentum and therefore, the velocity will be low, and the bus will still move further after applying the breaks
4) According to Newton's first law of motion, the conditions under which the acceleration of a moving object will be zero includes conditions where there are no resultant forces acting on the object.
For each of the following statements about deep-water waves, determine if the statement is true or false, then explain why: The longer the wave, the deeper the wave base. The greater the wave height, the deeper the wave base. The longer the wave, the faster the wave travels. The greater the wave height, the faster the wave travels. The faster the wave, the greater the wave height.
Answer:
The longer the wave, the deeper the wave base - True
The greater the wave height, the deeper the wave base - false
The longer the wave, the faster the wave travels- true
The greater the wave height, the faster the wave travels- false
The faster the wave, the greater the wave height - False
Explanation:
When a wave has a high length it means that the wave base will be deeper.
The longer the wave, the deeper the wave base - True
When the weight height is big , the wave base will be deeper.
The greater the wave height, the deeper the wave base - false
The longer the wave, the faster the wave travels- true
The greater the wave height, the faster the wave travels- false
The faster the wave, the greater the wave height - False
The law of conservation of momentum states that the total momentum of interacting objects does not _____. This means the total momentum _____a collision or explosion is equal to the total momentum _____ a collision or explosion.
Answer:
The law of conservation of momentum states that the total momentum of interacting objects does not change. This means the total momentum before a collision or explosion is equal to the total momentum after a collision or explosion.
Answer:
The answer is
Explanation:
Change. Does not change.means.
Hope this helps....
Have a nice day!!!!
when do you use cos and sin in situations like these? is horizontal always cos and vertical always sin?
Answer:
yes
Explanation:
this is simple
the horizontal line is adjacent
the vertical line is opposite
recall that cos x=adj/hyp
adj=hyp(cos x)
while opp=hyp(sin x)
(a) Calculate the rate of heat conduction through house walls that are 13.0 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 120 m2 and their inside surface is at 18.0 oC, while their outside surface is at 5.0 oC. (b) How many 1-kW room heaters would be needed to balance the heat transfer due to conduction
Answer:
a. 960 W b. One 1 kW room heater
Explanation:
a. The rate of heat conduction P = kA(T₂ - T₁)/d where k = 2 × 0.040 W/m-K = 0.080 W/m-K since the thermal conductivity of glass wool is 0.040 W/m-K and that of the material is twice the thermal conductivity of glass wool, A = area of walls = 120 m², T₁ = outside surface temperature = 5.0 °C, T₂ = inside surface temperature = 18.0 °C and d = thickness of wall = 13.0 cm = 0.13 m
P = kA(T₂ - T₁)/d
= 0.080 W/m-K × 120 m²(18.0 °C - 5.0 °C)/0.13 m
= 9.6 Wm/K × 13 K/0.13 m
= 124.8 Wm/0.13 m
= 960 W
b. The number of 1 kW room heater required will be
n = rate of heat conduction/power of one room heater = 960 W/ 1 kW = 960 W/1000 W = 0.96 ≅ 1
So we need only one 1 kW room heater.
Which is the second step of the fusion process?
O
H+1H - ?H+e+ + v + energy
O 6(3H) +21_e) - He +24H) + energy + 2u
{H+1H He + energy
O
He He He + 1H+1H + energy
Answer:
The correct option is;
[tex]_{1}^{2}\textrm{He} + _{1}^{1}\textrm{H} \rightarrow _{3}^{2}\textrm{He} + energy[/tex]
Explanation:
The second step of the fusion process is the reaction (combination) where a Deuterium combines with a hydrogen to produce one helium 3, 3He, nucleus and a energy photon as follows;
[tex]_{1}^{2}\textrm{He} + _{1}^{1}\textrm{H} \rightarrow _{3}^{2}\textrm{He} +\gamma \ (energy)[/tex]
After which the produced Helium-3 combines to form the Helium nucleus an emit 2 protons
Steps 1 and 2 are take place two times (producing 26 MeV energy) before the step three (the combination of the formed helium-3) takes occurs.
Answer:
C on edge
Explanation:
Just did it and got it right :)
If 60 L of a gas are at 4 atm and 27 C °, what pressure would it have if the volume is 40 L 127 C °?
Answer:
8 atm
Explanation:
Ideal gas law:
PV = nRT
where P is pressure, V is volume, n is moles, R is universal gas constant, and T is absolute temperature.
If n is constant:
PV / T = PV / T
(4 atm) (60 L) / (27 + 273) K = P (40 L) / (127 + 273) K
0.8 atm = 0.1 P
P = 8 atm
which of the following are possible units for a spring constant? A. N/nm B. nm/N C. nm/J D. J/nm
Answer:
Since N/m is the unit of spring constant N/nm would be the possible unit for a spring constant.
A. N/nm is the possible unit for a spring constant.
Is spring constant in N m?The units at the spring regular are Newton/meter (N/m). The poor signal within the above equation is an indication that the direction that the spring stretches is opposite the path of the pressure that the spring exerts.
Because the force is measured in Newtons and the spring consistent is multiplied with the aid of the gap in meters, the spring constant need to have devices that get rid of meters, ensuing most effective force. The most effective devices that work for the spring regular are for that reason, Newtons in step with the meter.
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Seje
A burning electric bulb is a good example of a(an)... object.
2 points
illuminated
luminous
translucent
transparent
Clear selection
Can you help me answer this pls
Answer:
luminous bcz they emits light by their own and don't need other resources to emit light
give an example of a balanced force and explain what makes it a balanced force
Which of the following is a true statement about mass and weight? Mass is a measure of how much matter an object has, while weight is a measure of how much space the object takes up. Mass will not change based on location, while weight will change based on gravitational pull. Mass is a measure of a gravitational pull on an object, while weight is a measure of how much matter is an object has. Mass is proportional to the force of gravity, while weight is proportional to the amount of mass.
Answer:
Mass will not change based on location, while weight will change based on gravitational pull.
Explanation:
The formula for weight is mass*gravitational pull, hence weight changes based on gravitational pull
Mass will not change based on location, while weight will change based on gravitational pull. This is a true statement about mass and weight.
What are mass and weight?The most fundamental characteristic of matter is mass, which is one of the fundamental quantities in physics. Mass is a term used to describe how much matter is there in a body. The kilograms is the SI unit of mass (kg). A body's mass remains constant at all times.
The amount of weight t indicates how much gravity is pulling on a body. The weight formula is provided by: w = mg
Weight being a force The SI unit of weight is the Newton, which is also the same as the SI unit of force (N). When we look at how weight is expressed, we can see that it depends on both mass and the acceleration caused by gravity; while the mass may not change from one location to another, the acceleration caused by gravity does.
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A bullet of mass m, moving horizontally with speed u, meets a block of wood of mass M, travelling along the same line but in the opposite direction with speed ,U, and remains embedded in it. Show that the loss of kinetic energy is of the form 1/2kMm, where k is in terms of u, U, m, M and find the loss in KE when the bullet of mass 4.0g, travelling at 890ms^-1 hits a block of wood, mass 4.0kg moving at 7.0ms^-1
Answer:
Explanation:
First of all we shall calculate the velocity of composite mass . Let it be v . Applying law of conservation of momentum
mu - MU = ( m + M ) v
v = mu - MU / ( m + M )
loss of kinetic energy
= 1/ 2 mu² + 1/2 MU² - 1/2 ( M +m ) v²
= 1/ 2 mu² + 1/2 MU² - 1/2 ( M +m ) (mu - MU)² / ( m + M )²
= 1/ 2 mu² + 1/2 MU² - 1/2 (mu - MU)² / ( m + M )
= 1/2 [ m²u² + mMu² +mMU² + m²U² - m²u² - M²U² - 2 muMU ] / ( m + M )
= 1 / 2 [ mMu² + mMU² - 2 muMU ] / ( m + M )
= 1 / 2mM [ (u² + U² - 2 uU) / ( m + M )]
= 1/2 mM x k
where
k = [ (u² + U² - 2 uU) / ( m + M )]
Given
m = .004 kg
M = 4 kg
u = 890 ms⁻¹
U = 7 ms⁻¹
k = ( 890² + 7² - 2 x 890 x 7 ) / 4.004
= ( 792100 + 49 - 12460 ) / 4.004
= 194727.52
loss of kinetic energy
= 1/2 mM x k
= .5 x .004 x 4 x 194727.52
= 1557.82 J .
What does the cross sign in the middle mean???
it is called the proportionality sign.
read as
"R is proportional to l"
State 1 difference between 1 way rotary motion and reversible rotary motion
Answer:
The difference between One-way as well as reversible rotary motion is described below.
Explanation:
Unless rotary motions occur restricted to single direction exclusively (i.e. whether clockwise as well as anti-clockwise only), it is defined as another rotary 'one-way' motion.This motor establishes that continuously variable movement at 360 ° chemically guided is conceivable. The rotating is regulated, and for a particular direction, the biochemical occurrences guiding rotation become incredibly selective.Millimeters, centimeters, meters,
kilometers, inches, feet, and
miles are all examples of
plz help
Millimeters, centimeters, meters, kilometers, inches, feet, and miles are all examples of unit of length like: distance between two points and displacement of any object.
What is unit?The quantity with a constant magnitude that is used to measure the magnitudes of other quantities of the same type is referred to as a unit in physics.The formula: physical quantity = numerical value × unit. can be used to determine a physical quantity's magnitude.A unit shouldn't alter as time or environmental factors like pressure and temperature change.It ought to be precisely defined.It need to be readily available and repeatable.Meter is a Si unit of length whereas centimeter is CGS unit of length and Feet is FPS unit of lengths. Another units are also useful in measuring lengths.
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Describe the following as a (a) distance (b) speed (c) acceleration (d) force
6. Force
7 speed
8 distance
9 acceleration
Explain why stellar parallax cannot be used to measure the distance to other galaxies.
Answer:
1. a) Astronomers use the parallax method to measure the distance to nearby stars, but
we can’t use it to measure the distance to stars in other galaxies. Why not? Why isn’t the
parallax method useful for measuring the distances to stars in other galaxies?
They are so distant that the parallax is too small to be measured since parallax varies
inversely with distance.
b) Instead of the parallax method, we use the standard candle method to measure the
distance to stars in other galaxies. In particular, we use the standard candle method to
measure the distances to Cepheid variable stars in other galaxies. What is special about
Cepheid variable stars that makes them useful for this purpose?
We can figure out their luminosities from their periods of variation. Then if we measure
their fluxes we can calculate their distances.
2. a) From what were the protons and electrons in your body made, and roughly when
were they made?
They were made from energy (or gamma rays) very soon after the big bang (in the first
second). 400,000 years later they got together to make hydrogen atoms.
b) From what were the carbon atoms in your body made, and where were they made?
They were not made in the big bang. They were made much later inside of stars or in
supernovae. They were made by fusion from lighter atoms.
3. Make two sketches of the Milky Way Galaxy, one an edge-on view and one a face-on
view, labeling the various parts of the galaxy.
You should have labeled the
The pH scale is used to tell if a substance
is an acid or base. Substances with a pH
of 7 are neutral. An acid is anything
below 7 and a base is anything above 7.
Bleach has a pH of about 12. What type of
substance is bleach?
A. base
B. acid
C. neutral
Answer: Bleach is a base
Explanation: If bleach had a pH level of 12, a number above 7, than it is a base. Hope this helps!
