The change in heat q for the aluminum cup is 141 J.
What is Specific heat?A substance's heat capacity is the amount of heat needed to increase its overall temperature by one degree. The heat capacity is known as the specific heat capacity or the specific heat if the substance's mass is unity.
change in heat -
The amount of heat Q that is transported to create a temperature shift depends on the substance and phase involved, the mass of the system, and the magnitude of the temperature change. (A) The temperature change and the amount of heat transported are directly inversely related.
The answer's sign dig is determined by a calculation's lowest sign digits.
The solution will need 3 digits because the temperatures are provided with 3 significant digits and the specified heat has 3 significant digits (the mass has 4 significant digits).
31.91 g * 0.903 J/g-C * (26.1 - 21.2 C) = 141 J
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What is the instantaneous value of a 10 ampere peak sine wave at 0, 30, 45, 60, and 180 degrees?
The instantaneous value of a sinusoidal waveform is the value of the alternating function at any particular instant.
The instantaneous value of a 10 ampere peak sine wave at 0, 30, 45, 60, and 180 degree are 0 A, 5 A, 7.07 A, 8.66 A, 0 A respectively.
From the question,
Instantaneous value is given as 10 A
The instantaneous value of a sine waveform is determined by the relation,
Instantaneous value = Peak value x sin θ
Substituting values in the above equation;
For 0°⇒
instantaneous value = 10 x sin 0°
= 10 x 0
= 0 A
For 30°⇒
instantaneous value = 10 x sin 30°
= 10 x (1/2)
= 5 A
For 45°⇒
instantaneous value = 10 x sin 45°
= 10 x (1/√2)
= 10 x 0.707
= 7.07 A
For 60° ⇒
instantaneous value = 10 x sin 60°
= 10 x (√3 / 2 )
= 10 x 0.866
= 8.66 A
For 180° ⇒
instantaneous value = 10 x sin 180°
= 10 x 0
= 0 A
Hence the instantaneous value of a 10 ampere peak sine wave at 0, 30, 45, 60, and 180 degree are 0 A, 5 A, 7.07 A, 8.66 A, 0 A respectively.
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The _ states that the forces that are changing Earth's surface today are the same forces that changed Earth's surface in the past
The uniformitarianism states that the forces that are changing Earth's surface today are the same forces that changed Earth's surface in the past as a result of the same types of agents being present all along.
What is uniformitarianism?This type of doctrine talks about how the earth's geologic processes are the same as a result of the agents of weathering such as glacier, wind etc being the same in this type of scenario.
Weathering is referred to the process in which rocks are broken down into smaller particles to form soil. The agents of weathering has been the same today and in the past which makes it constant.
This is therefore the reason why Uniformitarianism was chosen as the most appropriate choice.
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A film of soapy water (n = 1. 33) on top of a plastic cutting board (n > 1. 33) has a thickness of 147 nm. what color is most strongly reflected if it is illuminated perpendicular to its surface?
A film of soapy water (n = 1. 33) on top of a plastic cutting board (n > 1. 33) has a thickness of 147 nm. The color that is most strongly reflected if it is illuminated perpendicular to its surface is 294nm.
When the light is reflected it experiences a half of phase change. Then, the ray will be refracted by travelling through the soapy water down due to the refractive index. It will hit the second boundary which is plastic but light does not pass through the plastic. This will again reflect with again half of a phase change.
So, the formula used is:
2t = λ / 2 + λ / 2
Given,
refractive index of soap = 1.33
refractive index of air = 1
The relation between the thickness of the board and the wavelength used is as follows:
2t = λ / 2 + λ / 2
where, t is the thickness
λ is wavelength
On solving,
2t = λ
On substituting in above equation,
2(147) = λ
λ = 294nm
The color that is most strongly reflected if it is illuminated perpendicular to its surface is 294nm.
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At resonance, a driven rlcrlc circuit has vcvc = 5. 0 vv , vrvr = 8. 0 vv , and vlvl = 5. 0 vv. part a what is the peak voltage across the entire circuit?
At resonance, a driven rlcrlc circuit has vcvc = 5. 0 vv , vrvr = 8. 0 vv , and vlvl = 5. 0 vv having a peak voltage across the entire circuit
For any voltage waveform, the peak voltage is the highest point or voltage value. When Pulse Width Modulation (PWM) devices, like variable frequency drives, are added to a power system with a peak voltage that is equal to the square root of two times the RMS voltage, a power quality problem results.
Find the peak voltage, for instance, if the RMS voltage is 85 V. The average voltage and maximum voltage of AC power coming from the wall are both about 110 V. Therefore, the real peak voltage is 120/0.707 = 170 V. The sinusoid's amplitude is divided in half by this. Peak-to-peak voltage (Vp-p), also known as the total amplitude, is 340 V, or twice the peak voltage.
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write the factors of which affect pressure
Answer:
They are:
1. Height of liquid
2. Density of liquid
3. Acceleration due to gravity
A rubber ball is dropped on the floor. The rebound speed is one-half the speed it had just before hitting the floor. It will rise to ________ of the original height from which it was dropped. Group of answer choices 1/3 1/8 1/6 1/4 1/5
Since the rebound speed is one-half the speed it had just before hitting the floor, it will rise to 1/4 of the original height from which it was dropped; option C.
What is rebound speed?Rebound speed refers to the speed at which a body when it hits a surface is returned or rebounded to the original direction in which it comes from.
When objects are released from a height and allowed to hit the floor, some of the original energy of the object is converted to heat and sound, thus the object will rebound with a lesser speed and to a smaller height than from which it is released.
In the case of a rubber ball which is dropped on the floor. The rebound speed is one-half the speed it had just before hitting the floor.
Therefore, the height will be one-quarter the original height.
In conclusion, the rebounding of a ball is to a lesser height than the original height.
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1. Consider the potential energy diagram shown below. This graph shows the chemical potential energy in a reaction system over time. The y-axis is potential energy in kilojoules. The x-axis is the reaction progress or time.
Does this graph represent an endothermic or an exothermic reaction? Explain your answer.
What is the enthalpy change, ΔH, for this reaction? Show your work.
What is the activation energy, Ea, for this reaction? Show your work.
THE GRAPH IS BELOW
150 kJ of energy was given out over the course of the reaction and 200kJ is required for the reactants to be converted into products.
What is the potential energy graph?We know that the combination of the reactants is what leads to the formation of products. The interaction of the reactants and the products is what is shown on the potential energy curve. The hump at the highest point of the graph is the activation energy while the difference between the energy of the reactant and the products is the enthalpy of the reaction.
Now; the enthalpy change is given as;
ΔH = 200 kJ - 50 kJ = 150 kJ
Ea = 250 kJ - 50 kJ = 200kJ
We can see that 150 kJ of energy was given out over the course of the reaction and 200kJ is required for the reactants to be converted into products.
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Gold’s natural state has a shape and a define volume that is gold’s natural state
Answer:
Gold's natural state has a definite shape and a definite volume. Gold's natural state is solid.In nature, gold most often occurs in metallic form, alloyed with silver.450n 360n 710n 1400n 230n a block is placed in oscillation on a frictionless horizontal surface attached to a spring that is also attached to a wall. If, when stretched away from equilibrium by 15cm and released, it oscillates with a period of 0. 25s, and if the mass of the block is 15kg, what force was required to stretch the spring by the initial 15cm?.
F = 1420 N
Force was required to stretch the spring by the initial 15cm is 1420 N.
m = 15, P = 0.25, x = 0.15
F = -K x for spring
where,
F = force
K = constant
ω = (K/m)^1/2
where,
ω = angular frequency
m = mass of the block
ω^2 = K / m
K = m ω^2 = m (2 π f)^2 = m 4 π^2 / P^2
K = 4 π^2 m / P^2
F = K x = x * 4 π^2 m / P^2
F = 0.15 * 4 * π^2 * 15 / 0.25^2
F = 1420 N
What is oscillation?The movement between two locations back and forth, or to swing back and forth like a pendulum is known as oscillation.
What is equilibrium?A condition where competing forces or actions are in balance is called equilibrium.
What is the stretching force?Tensional force is the force exerted by a stretched item. It could be a rope, string, elastic band, or wire that is being stretched. The object's tensional force is applied to the objects stretching it. The stretched object is subject to tensile force.Exactly why does a spring stretch?A typical spring is a tightly wrapped metal coil or spiral that stretches when pulled (by applying force) and returns to its original shape when released (remove the force). A spring is elastic, in other words.To learn more about forced for stretching visit:
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An inductor is connected to an ac generator. part a as the generator's frequency is increased, what happens to the current in the inductor?
An inductor is connected to an ac generator. As the generator's frequency increases, the current in the inductor decreases.
Inductors and chokes are basically coils or loops of wire that are either wound around a hollow tube former (air cored) or wound around some ferromagnetic material (iron cored) to increase their inductive value called inductance.
Inductors store their energy in the form of a magnetic field that is created when a voltage is applied across the terminals of an inductor.
The growth of the current flowing through the inductor is not instant but is determined by the inductors own self-induced or back emf value. Then for an inductor coil, this back emf voltage VL is proportional to the rate of change of the current flowing through it.
This current will continue to rise until it reaches its maximum steady state condition which is around five time constants when this self-induced back emf has decayed to zero. At this point a steady state current is flowing through the coil, no more back emf is induced to oppose the current flow and therefore, the coil acts more like a short circuit allowing maximum current to flow through it.
However, in an alternating current circuit which contains an AC Inductance, the flow of current through an inductor behaves very differently to that of a steady state DC voltage. Now in an AC circuit, the opposition to the current flowing through the coils windings not only depends upon the inductance of the coil but also the frequency of the applied voltage waveform as it varies from its positive to negative values.
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Katie rolls a toy car off the end of a table.
Answer:
The toy car will fall off Katie's hands and onto the ground .
Explanation:
This happens due to gravity.
The transistor is a great improvement over the vacuum tube because it is much more energy efficient.
a. true or
b. false
The transistor is a great improvement over the vacuum tube because it is much more energy efficient is a True statement .
A transistor is a miniature semiconductor that controls current or voltage flow and also amplifies and generates electrical signals and can also act as a switch/gate for them.
A vacuum tube, also called a valve in British English, is an electronic device used in many older model radios, television sets, and amplifiers to control electric current flow. The cathode is heated, as in a light bulb, so it will emit electrons. This is called thermionic emission.
Transistors consume lower power consumption , less waste heat, and are highly efficient than equivalent tubes, especially in small-signal circuits.
Vacuum tubes runs with D.C voltage which ranges from 400 V to 500 V. Vacuum tubes require much higher power than transistor device. Hence , are less efficient . This is the main advantages of the transistor.
Another advantage of transistors are that they are portable and lightweight equipment. Can operate on lower-voltage supplies for greater safety, also have lower costs and tighter clearances.
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In a ruby laser, an electron jumps from a higher energy level to a lower one. if the energy difference between the two levels is 1. 8 ev, what is the wavelength of the emitted photon?
The wavelength of the emitted photon is([tex]\lambda[/tex])= 690nm
How can we calculate the wavelength of the emitted photon?To calculate the wavelength of the photon we are using the formula,
[tex]\triangle E= \frac{h\times c}{\lambda}[/tex]
Or,[tex]\lambda= \frac{h\times c}{\triangle E}[/tex]
We are given here,
[tex]\triangle E[/tex]= The energy difference between the two levels = 1. 8 ev= [tex]1.8\times 1.6 \times 10^{-19}[/tex] C.
h= Planck constant = [tex]6.626\times 10^{-34}[/tex] Js.
c= speed of light = [tex]3\times10^8[/tex] m/s.
We have to find the wavelength of the emitted photon =[tex]\lambda[/tex] m.
Therefore, we substitute the known parameters in the above equation, we can find that,
[tex]\lambda= \frac{h\times c}{\triangle E}[/tex]
Or,[tex]\lambda= \frac{6.626\times 10^{-34}\times 3\times 10^8}{1.8\times 1.6 \times 10^{-19}}[/tex]
Or,[tex]\lambda= 690\times 10^{-9}[/tex] m
Or,[tex]\lambda[/tex]=690 nm.
From the above calculation we can conclude that the wavelength of the emitted photon is 690nm.
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A child has an ear canal that is 1. 3 cm long. at what sound frequencies in the audible range will the child have increased hearing sensitivity?
A child has an ear canal that is 1. 3 cm long. Sound frequencies in the audible range for the child to have increased hearing sensitivity is 6600 Hz to 19,800 Hz
The shape of the human ear is similar to a pipe that has a closed end and other end is open. Hence,
λ = 4L where L is the length of child's ear
Wavelength, λ = 4 × Length of the ear of the child
λ = 4 × 0.013m
λ = 0.052m
Frequency is the no. of oscillations per unit time.
The frequency of the sound, ν = c/λ
where c is the speed of sound i.e. 343 m/s
λ is the wavelength of sound
The child's audible range is equal to
ν = 343/0.052
ν = 6600Hz
We can also say that, ν is 13200 Hz or 19,800 Hz.
In general, the audible range of frequency for human ear is 20Hz to 20,000Hz.
Hence, sound frequencies in the audible range will the child have increased hearing sensitivity is 6600Hz to 19800 Hz.
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A carnival ride accelerates upwards at 2.5 m/s. what is the apparent weight of a 35 kg child on the ride
The apparent weight of the child is 437.5 N.
Calculation:The weight of a person/object moving up with an acceleration "a" is given by
W = m (g + a)
where,
W = apparent weight
m = mass of the person/object
g = acceleration due to gravity = 10 m/s²
a = acceleration of the object/person
Given,
m = 35 kg
a = 2.5 m/s²
To find,
W =?
Put the value sin the formula,
W = m (g + a)
W = 35 (10 + 2.5)
= 35 (12.5)
= 437.5 N
Therefore, the apparent weight of the child is 437.5 N.
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A proton moving at 7. 0 × 10^4 m/s horizontally enters a region where a magnetic field of 0. 10 t is present, directed vertically downward. What magnitude force acts on the proton due to this field?
A proton moving at 7. 0 × 10^4 m/s horizontally enters a region where a magnetic field of 0. 10 t is present, directed vertically downward. The magnitude force acts on the proton due to this field will be 1.12 * [tex]10^{-23}[/tex] N
Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion.
Force in a magnetic field = q. ( v * B )
where
q = charge of particle = 1.6 * [tex]10^{-27}[/tex] C
v = velocity of particle = 7. 0 × [tex]10^{4}[/tex] m/s
B = 0. 10 T
Force = 1.6 * [tex]10^{-27}[/tex] * 7. 0 × [tex]10^{4}[/tex] * 0. 10
= 1.12 * [tex]10^{-23}[/tex] N
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what is the best estimate for the product 2,704.241 X 165.9
The best estimate for the product of 2,704.241 and 165.9 is determined as 448,633.58.
What is product of numbers?The product of numbers is the multiplication of two or more integers together.
Product of the given numberThe product of the given numbers is calculated as shown blow.
The best estimate for the product of 2,704.241 and 165.9.
= 2,704.241 X 165.9
= 448,633.58
Thus, the best estimate for the product of 2,704.241 and 165.9 is determined as 448,633.58.
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What happens to the visible radiation produced by new stars within a molecular cloud?
The visible radiation produced by new stars within a molecular cloud get absorbed by dust grains and heats up the cloud
A molecular cloud is an interstellar cloud of gas and dust in which molecules can form, the most common of which is hydrogen .
The formation of stars occurs exclusively within molecular clouds because of their low temperatures and high densities, because the gravitational force acting to collapse the cloud must exceed the internal pressures that are acting "outward" to prevent a collapse.
Visible radiation are absorbed by dust grains and heats up the cloud as it cannot penetrate through the cloud instead get absorbed by the cloud . Newly formed stars are visible nearby, their images reddened by blue light which got scattered by the pervasive dust.
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What must you do at a flashing red light? * 1 point slow down and proceed with caution be ready for a traffic light ahead stop and wait until the light stops flashing stop and proceed only when clear
Stop and wait until the light stops flashing stop and proceed only when clear.
Flashing Red - A flashing red traffic signal light means "STOP." After stopping, you may proceed when it is safe.
How must you react to a flashing red traffic light?
Flashing Red: If the traffic signal is flashing red, treat it as a stop sign and come to a complete stop at the intersection. Look carefully in all directions before proceeding. Other directions may have a different type of signal indication.What must a driver do at a flashing yellow light ?
A flashing yellow light warns drivers to slow down and proceed with caution. Drivers may turn left on a green light. However, drivers must yield the right-of-way if other traffic is approaching from the opposite direction.Learn more about traffic lights
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What is the mathematical relationship between wavelength and energy transmission?.
The mathematical relationship between wavelength and energy transmission E = hv.
What is Wavelength and Energy transmission?A waveform signal that is carried in space or down a wire has a wavelength, which is the separation between two identical places (adjacent crests) in the consecutive cycles. This length is often defined in wireless systems in metres (m), centimetres (cm), or millimetres (mm) (mm). The wavelength is most frequently described in nanometers (nm), which are units of 10⁻⁹ m, or angstroms (Å), which are units of 10⁻¹⁰ m, for infrared (IR), visible light (UV), and gamma radiation (γ).
The most fundamental aspect of global energy integration is energy transmission. With the flow of electricity produced from coal as well as from hydro, nuclear, wind, and solar energy all being transported through power networks, electric energy transmission is a significant source of energy transport.
Wavelength and frequency are connected to energy in the same way as they are to light. Greater energy is correlated with shorter wavelengths and higher frequencies. Therefore, lower energy is produced by longer wavelengths and lower frequencies. E = hv is the energy equation.
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The colors of a soap bubble or oil slick are due to __________. two-slit interference thin-film interference huygens' principle diffraction
Answer:
Thin film interference
Does the youth service project, or a civic organisation, or community service centre shows signs of strength?yes/no
Answer:
Yes
Explanation:
This helps youngsters be empathetic citizens
A town's vitality may be measured by the sensation of a youth service initiative organized by a civic group or community service center. The given statement exists true.
Exactly what does it mean when someone says they belong to a civic group?The word "civic organization" directs to any group of people in a community whose primary mission exists to encourage civic, philanthropic, or religious causes.
Youth involvement in the development, monitoring, reporting, and evaluation of devices, tactics, and programs may increase their likelihood of experiencing.
In conclusion, the strength may be displayed in the youth service initiative of a civic organization or a community service center. It showed what young people can do when they enact together. Education and capacity development are two methods that have been shown to improve youth engagement.
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A sound wave leaves the loudspeaker. As it travels, it experiences a temporary increase in wavelength and then returns to its original wavelength. Which of the following scenarios could explain this change in wavelength? Select ALL that apply.
A
The sound wave traveled into the rocky ground.
B
The sound wave traveled through a glass of water.
C
The sound wave reflected off of a rock wall nearby.
D
The sound wave traveled through a person walking along the shore.
E
The sound wave traveled through a helium balloon (helium is less dense than air).
A sound wave leaves the loudspeaker. As it travels, it experiences a temporary increase in wavelength and then returns to its original wavelength. The sound wave traveled through a helium balloon (helium is less dense than air could explain this change in wavelength
The pattern of disruption brought on by energy moving away from the sound source is known as a sound wave. Longitudinal waves are what makeup sound. This indicates that the direction of energy wave propagation and particle vibrational propagation are parallel. The atoms oscillate when they are put into vibration.
A high-pressure and a low-pressure zone are created in the medium as a result of this constant back and forth action. Compressions and rarefactions, respectively, are terms used to describe these high- and low-pressure zones. The sound waves go from one medium to another as a result of these regions being transmitted to the surrounding media.
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What is the maximum size of a three-phase, 240-volt motor that can be controlled using a size 2 nema contactor?
15 HP at 240 V is the maximum size of a three-phase, 240-volt motor that can be controlled using a size 2 NEMA contactor
This is further explained below.
What is a NEMA contactor?Generally, Size 2 NEMA contactors can only handle three-phase, 240-volt motors up to 15 horsepower at 240 volts.
In conclusion, Contactors and motor starters produced by NEMA (National Electrical Manufacturers Association) are graded according to their sizes. These sizes are categorized according to the current and power ratings that they carry.
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(b) A ball is thrown vertically upwards with
velocity of 20 m/s from the top of a tower of
height 25 m from ground. How long does it
remain in air? (g = 10 m/s²)
Answer:
5 seconds
Explanation:
The vertical position of the ball will be given by the equation
df = do + vo t + 1/2 a t^2 df = final position = 0 ( on the ground
do = original position ( 25 m )
vo = original velocity (+ 20 m/s)
a = - 10 m/s^2
So this becomes
0 = 25 + 20 t - 1/2 (10)t^2
= - 5 t^2 +20 t + 25 Use Quadratic Formula a = -5 b=20 c = 25
to find the positive value of t = 5 seconds
If the ambulance siren was emitting a crest at time = 0, what is the siren doing at time = 0. 02 s? is it emitting a crest or trough, or is it somewhere else in the cycle? how do you know?
while the siren produces waves of constant frequency, as it approaches us the observed frequency increases and our ear hears a higher pitch. After it has passed us and is moving away, the observed frequency and pitch drop this effect is known as Doppler effect.
The characteristic sound of a motorcycle buzzing by is an example of the Doppler effect. Specifically, if you are standing on a street corner and observe an ambulance with a siren sounding passing at a constant speed, you notice two characteristic changes in the sound of the siren. First, the sound increases in loudness as the ambulance approaches and decreases in loudness as it moves away, which is expected. But in addition, the high-pitched siren shifts dramatically to a lower-pitched sound.
what is Doppler effect?
The Doppler effect is an alteration in the observed frequency of a sound due to motion of either the source or the observer. Although less familiar, this effect is easily noticed for a stationary source and moving observer.
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What is the inductance of a coil if the coil produces an emf of 2.50 v when the current in it changes from -28.0 ma to 25.0 ma in 12.0 ms?
The inductance of a coil if the coil produces an emf of 2.50 v when the current in it changes from -28.0 ma to 25.0 ma in 12.0 ms is L = 0.566 H
An inductor is a passive electronic component that stores energy in the form of a magnetic field. In its simplest form, an inductor consists of a wire loop or coil. The inductance is directly proportional to the number of turns in the coil.
The SI unit of inductance is Henry abbreviated as 'H'. It is defined as the measure of electric current changes at one ampere per second resulting in an electromotive force of one volt across the inductor.
The expression for induced emf
E=−L (di /dt)
L= E (dt / di )
di = 25 - ( -28) = 53 mA = 53 * [tex]10^{-3}[/tex] A
dt = 12 ms = 12 * [tex]10^{-3}[/tex] sec
E = 2.5 V
L = 2.5 ( 12 * [tex]10^{-3}[/tex] / 53 * [tex]10^{-3}[/tex] )
L = 0.566 H
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. Barium has a work function of 2.48eV. What is the maximum kinetic energy if the metal is illuminated by UV light of wavelength 365nm?
The maximum kinetic energy is 0.91 eV
What is Work Function of a Metal ?A Work Function of a Metal is the minimum energy required to liberate an electron from a metal surface. From the formula;
hF = hf + E
hF = energy for liberation or illuminationhf = work function = 2.8 eVE = kinetic energyGiven that a Barium has a work function of 2.48eV. What is the maximum kinetic energy ?
Convert eV to Joule by multiplying by 1.6 x [tex]10^{-19}[/tex]
hf = 2.48 x 1.6 x [tex]10^{-19}[/tex]
hf = 3.968 x [tex]10^{-19}[/tex] J
If the metal is illuminated by UV light of wavelength 365nm,
E = hF = hc/λ
Where
C = speed of light = 3 x [tex]10^{8}[/tex] m/sh = Planck constant = 6.6 x [tex]10^{-34}[/tex] Jsλ = wavelength = 365 x [tex]10^{-9}[/tex] mSubstitute all the parameters
hF = (6.6 x [tex]10^{-34}[/tex] x 3 x [tex]10^{8}[/tex]) / 365 x [tex]10^{-9}[/tex]
hF = 1.98 x [tex]10^{-25}[/tex] / 365 x [tex]10^{-9}[/tex]
hF = 5.42 x [tex]10^{-19}[/tex] Joule
The maximum kinetic energy will be
hF = hf + E
Make E the subject of formula
E = hF - hf
E = 5.42 x [tex]10^{-19}[/tex] - 3.968 x [tex]10^{-19}[/tex]
E = 1.452 x [tex]10^{-19}[/tex] J
Convert Joule back to eV by dividing by 1.6 x [tex]10^{-19}[/tex]
E = 1.452 x [tex]10^{-19}[/tex] / 1.6 x [tex]10^{-19}[/tex]
E = 0.9075 eV
Therefore, the maximum kinetic energy is 0.91 eV approximately
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Suppose that we repeat the experiment, except that we place the sodium flame in a strong, localized electric field. The field changes the energy levels of the sodium atom, but it does not affect the sodium in the lamp or the photons it produces. The shadow cast by the sodium flame when illuminated by the sodium lamp should?.
The shadow cast by the sodium flame when illuminated by the sodium lamp should become lighter.
What is Zero current point ?The interruption phenomenon in high power circuit breakers is referred to as current zero (CZ). Today, it is unlikely that high voltage circuits could be inexpensively disrupted using anything other than an electric arc.
electric field -
The electric force per unit charge is referred to as the electric field. It is assumed that the field's direction corresponds to the force it would apply on a positive test charge. From a positive point charge, the electric field radiates outward, and from a negative point charge, it radiates in.
In order to provide the lamp with a virtually constant current rather than a constant voltage in order to ensure reliable operation, the lamp is often supplied by an AC voltage source connected in series with an inductive ballast. To minimise resistive losses, the ballast is often inductive rather than just resistive. Because the sodium flame's shadow is growing lighter and this lamp's current is going toward its zero-current point.
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If a current of 2. 4 a is flowing in a wire of diameter 2. 0 mm, what is the average current density?
The average current density is 7.6 × 10⁵ A/m².
To calculate the current density current will be 2.4 A.
Diameter of a wire = 2mm.
The cross-sectional area of the wire is given by r = d/2
where r is the radius of the wire.
Then, the cross-sectional area is = 0.00000314159265
= 3.1 × 10⁻⁶ m².
What is average current density?Consider a current carrying conductor, the current density depends upon the current flow in the conductor. If the current flow in the conductor will be high then the current density will also be high. Using the average current flowing through the conductor, the average current density will be found.
Average current density j = I / A Ampere/ meter².
By substituting the values in the formula,
j = 2.4 / ( 3.1 × 10⁻⁶)
= 7.6 × 10⁵ A/m².
Hence, the current density can be calculated.
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