This question is incomplete, the complete question is;
In a simple model of a potassium iodide (KI) molecule, we assume the K and I atoms bond ionically by the transfer of one electron from K to I.
(a) The ionization energy of K is 4.34 eV, and the electron affinity of I is 3.06 eV. What energy is needed to transfer an electron from K to I, to form K+ and I- ions from neutral atoms? This quantity is sometimes called the activation energy Ea.eV
(b) A model potential energy function for the KI molecule is the Lennard - jones potential:
U(r) = 4∈[ (α/r)¹² - (α/r)⁶ ] + Ea
where r is the internuclear separation distance and α and ∈ are adjustable parameters (constants) . The Ea term is added to ensure the correct asymptotic behavior at large r and is activation energy calculated in a. At the equilibrium separation distance, r=r₀=0.305 nm, U(r) is a minimum, and dU/dr=0. In addition, U(r₀)=-3.37 eV.
Us the experimental values for the equilibrium sepeartion and dissociation energy of KI to determine/find 'α' and '∈'.
(c) calculate the force needed to break the KI molecule in nN
Answer:
a) energy is needed to transfer an electron from K to I, to form K+ and I- ions from neutral atoms is 1.28 eV
b) α = 0.272, ∈ = 4.65 eV
c) the force needed to break the KI molecule in nN 65.6 nN
Explanation:
a) The ionization energy of K is 4.34 ev ( energy needed to remove the outer most electrons)
And the electron affinity of I is 3.06 ev ( which is energy released when electron is added)
Now the energy that is need to transfer an electron from K to I,
i.e the ionization energy of K(4.34 ev) and the electron affinity of I (3.06 ev)
RE = 4.34 - 3.06 = 1.28 eV
b)
from the question we have
U(r) = 4∈[ (α/r)¹² - (α/r)⁶ ] + Ea
now taking d/drU(r₀)=0 (at r = r₀)
= 4∈d/dr [ (α/r)¹² - (α/r)⁶ ] = 0
= ( -12(α¹²/r¹³)) - (-6 (α⁶/r⁷)) = 0
12(α¹²/r¹³) = 6 (α⁶/r⁷)
α⁶ = r⁶/2
α = r/(2)^1/6
at equilibrium r = r₀ = 0.305 nm
α = 0.305 nm / (2)^1/6
C = 0.0305/1.1246
α = 0.272
Now substituting the values of U(r₀), α, Eₐ in the initial expression
U(r) = 4∈[ (α/r)¹² - (α/r)⁶ ] + Ea
we have
- 3.37eV = 4∈ [ (0.272 nm / 0.305 nm)¹² - (0.272 nm / 0.305 nm )⁶ ] + 1.28
- 1.65 eV = ∈(0.25 - 0.5)
∈ = 4.65 eV
c)
Now to break the molecule then the potential energy should be zero(0)
and we know r = 0.272 nm
therefore force needed to break the molecule is
F = -dU/dR_r-α
F = -4∈ (-12/α + 6/α)
F = -4(4.65eV) ( -12/0.272nm + 6/0.272nm)
F = 65.6 nN
An electron as q = 1.602 * 10-19 C is placed .03m away from spherical object with a net charge of -7.2 C.
A. What is the force exerted on the electron?
B. How strong is the electric field at the electron’s location?
C. How much work would be done on the electron if it was moved so that it’s .001m away from the sphere?
D. Now replace the electron with a positron (q = +1.602 × 10-19C). Explain.
Answer:
See explanation
Explanation:
The electric force exerted on the electron is given by Coulomb's law;
F= KqQ/r^2
F= force on the electron
K= constant of Coulomb's law
q= charge on the electron
Q=charge on the spherical object
r= distance between the charges
F= 9×10^9 × -1.602 × 10^-19 × (-7.2)/(0.03)^2
F= 103.8 × 10^-10/9×10^-4
F= 11.53 ×10^-6
F= 1.153 ×10^-5 N
The force in this case is repulsive
E= F/q
E= 1.153 ×10^-5 N/ 1.602 * 10-19 C
E= 0.719 × 10^14
E= 7.19 × 10^13 NC-1
The electro field around the electron is very strong.
c)
V= Kq/r
V= 9×10^9 × 1.602 × 10^-19/0.001
V= 14418 × 10^-10
V=1.4418 ×10^-6 V
W= qV
W= 1.602×10^-19 C × 1.4418 ×10^-6 V
W= 2.31 ×10^-25 J
Replacing the electron with a positron
F= 9×10^9 × 1.602 × 10^-19 × (-7.2)/(0.03)^2
F= 103.8 × 10^-10/9×10^-4
F= 11.53 ×10^-6
F= -1.153 ×10^-5 N
The force in this case is attractive
A constant force of 5KN pulls a crate along a distance of 15 m in 75s.What is the power
Explanation:
We know,
1KN = 1000N
Then, Force(F) = 5*1000N
=5000N
Here,
Power (P)=Work(W)/Time(T)
=Force * distance/ Time (W = F*s)
= 5000*15/75
=1000
So, The power of body or object is 1000Watt.
I hope this will be helpful for you.
A superball has a coefficient of restitution of .90. The ball is dropped from an intitial height of 1.60m.
a) if the ball is allowed to bounce 3 times, how high will it rebound after the third bounce?
b) If the ball has a mass of 48g, calculate the amount of the ball's orignal energy that was lost in the three impacts with the floor.
Answer:
a
[tex]H_3 = 0.85 \ m[/tex]
b
[tex]PE = 0.3528 \ J[/tex]
Explanation:
From the question we are told that
The coefficient of resolution is [tex]C_r = 0.90[/tex]
The initial height is [tex]H_i = 1.60 \ m[/tex]
Considering question a
The number of times the ball bounced is [tex]k = 3[/tex]
Generally the height attained after the 3rd bounce is mathematically represented as
[tex]H_3 = H_i * (C_r)^{2 * k }[/tex]
=> [tex]H_3 = 1.60 * 0.90^{2 * 3 }[/tex]
=> [tex]H_3 = 0.85 \ m[/tex]
Considering question b
The mass is m = 48 g = 0.048 kg
Generally the amount of potential energy that was lost is mathematically represented as
[tex]PE = mg [ H_i - H_3 ][/tex]
=> [tex]PE = 0.048 * 9.8 [1.60 - 0.85 ][/tex]
=> [tex]PE = 0.3528 \ J[/tex]
Imagine you derive the following expression by analyzing the physics of a particular system: M= (mv2r)(mGr2). Simplify the expression for M using the techniques mentioned above.
Answer:
The simplified expression is [tex]M = \frac{v^2 r}{G}[/tex]
Explanation:
From the question we are told that
[tex]M = \frac{ \frac{m v^2}{r} }{\frac{ mG}{r^2 } }[/tex]
So simplifying we have
[tex]M = \frac{m v^2}{r} * \frac{r^2 }{ mG }[/tex]
[tex]M = \frac{v^2 r}{G}[/tex]
Thus the simplified formula is [tex]M = \frac{v^2 r}{G}[/tex]
Unpolarized light with intensity 370W/m2 passes first through a polarizing filter with its axis vertical, then through a second polarizing filter. It emerges from the second filter with intensity 121W/m2 .
What is the angle from vertical of the axis of the second polarizing filter?
Express your answer to two significant figures and include the appropriate units
Answer:
Answer:
36°
Explanation:
Using
I= (1/2Io) cos²စ
Then Substituting
121W/m² = 1/2*370W/m²cos²စ
0.8086= cosစ
Cos^-1 0.8086= 36°
A ball is rolling down a hill. At one point near the top of the hill, it’s velocity is 2 m/s. Further down the hill, it’s velocity is 9 m/s what is tringlev?
Explanation:
The change in velocity is the final velocity minus the initial velocity.
Δv = v − v₀
Δv = 9 m/s − 2 m/s
Δv = 7 m/s
If you travel 5 miles north then turn and travel 5 miles south, you have traveled ______ miles
Answer: 10 miles
Explanation:
5 miles +5 miles= 10 miles (despite the directions)
This is the distance traveled
-------------------------------------
EXTRA STUFF ( you can literally ignore this part)
If you are asked for displacement instead for distance, then it will be 0 miles because you went 5 miles north and 5 miles south, which at the end, you are still at where you originally were.
Hope this helps!! :)
Cousin Throckmorton is playing with the clothesline. One end of the clothesline is attached to a vertical post. Throcky holds the other end loosely in his hand, so that the speed of waves on the clothesline is a relatively slow 0.700 m/s . He finds several frequencies at which he can oscillate his end of the clothesline so that a light clothespin 40.0 cm from the post doesn't move. What are these frequencies?
Answer:
The frequencies are [tex]f_n = n (0.875 )[/tex]
Explanation:
From the question we are told that
The speed of the wave is [tex]v = 0.700 \ m/s[/tex]
The length of vibrating clothesline is [tex]L = 40.0 \ cm = 0.4 \ m[/tex]
Generally the fundamental frequency is mathematically represented as
[tex]f = \frac{v}{2 L }[/tex]
=> [tex]f = \frac{ 0.700 }{2 * 0.4 }[/tex]
=> [tex]f = 0.875 \ Hz[/tex]
Now this other frequencies of vibration experience by the clotheslines are know as harmonics and they are obtained by integer multiple of the fundamental frequency
So
The frequencies are mathematically represented as
[tex]f_n = n * f[/tex]
=> [tex]f_n = n (0.875 )[/tex]
Where n = 1, 2, 3 ....
A series RLC circuit connected across an ac voltage source has minimum current flowing through the circuit when operating at the resonant frequency. is this statement true or false and why?
Answer:
False
Explanation:
This is because Since the current flowing through a series resonance circuit is the product of voltage divided by impedance, at resonance the impedance, Z is at its minimum value, ( =R ). So, the circuit current at this frequency will be at its maximum value of V/R
What is the term for when the positive side of a battery is connected to the acceptor side and the negative side is connected to the donor side of the p-n rectifying junction?
Answer:
It is called Reverse biased
Explanation:
It is reverse bias because the voltage potential side of the battery is connected negative to the donor side or p type material and it is connected positive to the N type material or acceptor side across the diode which increases the diode width of the PN junction.
Two lasers are shining on a double slit, with slit separation d. Laser 1 has a wavelength of d/20, whereas laser 2 has a wavelength of d/15. The lasers produce separate interference patterns on a screen a distance 6.00 m away from the slits.
Which laser has its first maximum closer to the central maximum?
What is the distance Image for Two lasers are shining on a double slit, with slit separation d. Laser 1 has a wavelength of d/20, whereas las between the first maxima (on the same side of the central maximum) of the two patterns?
Two lasers are shining on a double slit, with slit separation d. Laser 1 has a wavelength of d/20, whereas las= ______ m
What is the distance Deltay_max-min between the second maximum of laser 1 and the third minimum of laser 2, on the same side of the central maximum?
Deltay_max-min = ______ m
Answer:
A) Therefore laser1 has the maximum closest to the central maximum
B) Δₓ = 0.8
Explanation:
A) The expression for the constructive interference of a double slit is
d sin θ = m λ
let's use trigonometry to find the angle
tan θ = y / L
in interference phenomena the angles are small
tan θ = sin θ / cos θ = sin θ
sin θ = y / L
we subjugate
d y / L = m λ
y = m λ L / d
let's apply this equation for each case
a) Lares 1 has a wavelength λ₁ = d / 20, the screen is at L = 6.00 m
they ask us for the first axiom m = 1,
let's calculate
y₁ = 1 (d / 20) 6.00 / d
y₁ = 0.3
Laser 2, λ₂ = d / 15
λ₂ = 1 (d / 15) 6.00 / d
λ₂ = 0.4
Therefore laser1 has the maximum closest to the central maximum
b) let's find the distance of each requested value
second maximum m = 2 of laser 1
yi '= 2 (d / 20) 6 / d
y1 '= 0.6
3rd minimum of laser 2
the expression for destructive interference is
d sinθ = (m + 1/2) lam
y = (m ) λ L / d
in this case m = 3
let's calculate
y2 '= (3+0.5) (d / 15) 6 / d
y2 '=21/15
They ask us for the dalt of these interference
Δₓ = y3 -y2'
Δₓ = 21/15 - 0.6
Δₓ = 0.8
A coil has an inductance of 7.00 mH, and the current in it changes from 0.200 A to 1.50 A in a time interval of 0.250 s. Find the magnitude of the average induced emf in the coil during this time interval.
Answer:
Magnitude of the average induced emf = 36.4 mv
Explanation:
Given:
inductance of the coil (L) = 7 mH
Initial current (Ci) = 0.200 A
Final current (Cf) = 1.50 A
Interval = 0.250 s
Find:
Magnitude of the average induced emf
Computation:
E = L(di/dt)
E = 7 [(1.5-0.20) / 0.250]
E = 7[5.2]
Magnitude of the average induced emf = 36.4 mv
How many (whole number of) 87 kg people
can safely occupy an elevator that can hold a
maximum mass of exactly 1 metric ton? A
metric ton is 1.000 x 103 kg.
Answer in units of people.
Answer:
11
Explanation:
1. You are going to be rounding down.
2. change the metric ton to kg.
1.000 * 10^3 kg = 1000 kg
1000 / 87 = 11.49 = 11 people
In what way is the study of psychology similar to other “hard sciences”? A. use of the scientific method B. use of memory C. use of emotion D. use of behavior
Answer:
The correct option is a
Explanation:
Psychology can be defined as the "scientific study" of the mind and behavior of humans and other animals. It involves the use of scientific methods in determining or understanding the social, physiological and biological behaviors in different groups or individual organisms
The correct option is a
The following information should be considered:
Psychology refers to the "scientific study" of the mind & behavior of humans and other animals. It includes the use of scientific methods in measurement or understanding the social, physiological ,and biological behaviors in different groups or individual organisms.Learn more: https://brainly.com/question/17429689?referrer=searchResults
A helicopter blade spins at exactly 180 revolutions per minute. Its tip is 10.00 m from the center of rotation. What is its average velocity over one revolution
Answer:
5.8E-3m/s
Explanation:
Using
V= d/t
V= velocity
d= distance
t= time
But d= 2πr
But 180rev= 1min
So 1min/180= 60s/180
So
Vavr= 2π(10m)/180*60
=5.8E-3m/s
An object is moving with constant non-zero velocity. Which of the following statements about it must be true?
(A) A constant force is being applied to it in the direction of motion.
(B) A constant force is being applied to it in the direction opposite of motion.
(C) A constant force is being applied to it perpendicular to the direction of motion.
(D) The net force on the object is zero.
(E) Its acceleration is in the same direction as its velocity.
Answer:
The net force on the object is zero.
Explanation:
An object is moving with constant non-zero velocity. If velocity is constant, it means that the change in velocity is equal to 0. As a result, acceleration of the object is equal to 0. Net force is the product of mass and acceleration. Hence, the correct option is (d) "The net force on the object is zero".
For a constant non-zero velocity the net force on the object is zero.
Velocity is defined as the change in displacement per change in time of motion.
[tex]v = \frac{\Delta x}{\Delta t}= \frac{x_2 - x_1}{t_2 - t_1}[/tex]
where;
Δx is the change in displacement
Δt is the change in time motion
When the change in the displacement is same for equal time interval, the resulting velocity will be constant but non-zero in magnitude.
Also, when the net force acting on an object is zero, the object will move with a constant velocity.
[tex]\Sigma F_x = 0[/tex]
Thus, for a constant non-zero velocity the net force on the object is zero.
Learn more here: https://brainly.com/question/20298765
A 26.5-mW laser beam of diameter 1.88 mm is reflected at normal incidence by a perfectly reflecting mirror. Calculate the radiation pressure on the mirror.
Answer:
Explanation:
Area= pier^2
=( 1.88/2)^2= 0.0000000314m^2
Intensity= 0.0265/0.000000314
= 7962W/m^2
Pressure= 2*7962)/345= 5.13*10^-5pa
A standard gold bar stored at Fort Knox, Kentucky, is 7.00 inches long, 3.63 inches wide, and 1.75 inches tall. Gold has a density of 19,300 kg/m3. What is the mass of such a gold bar?
Answer:
14.1 kg
Explanation:
Given:
Length=7.00inches
Width=3.63 inches
Height=1.75 inches
density = 19,300 kg/m3.
We can convert the given parameters to metre for unit consistency
But we know 1 inches= 0.0254 metre
✓Then Length l=7.00inches
=7×0.0254 metre=0.1778m
✓Width w =3.63 inches
==3.63 ×0.0254 metre=0.092m
✓Height h =1.75 inches
=1.75 ×0.0254 metre=0.0445 m
But Mass= density × volume
Volume= Length× width×height
Mass= density× Length× width×height
= 19300kg/m³×0.1778×0.0922×0.0445
=14.1 kg
Therefore, the mass of the gold bar is 14.1 kg
The mass of such a gold bar is of 13.89 kg.
Given data:
The length of gold bar is, [tex]L=7.00 \;\rm in =7.00 \times 0.0254=0.1778 \;\rm m[/tex].
The width of gold bar is, [tex]w= 3.63 \;\rm in =3.63 \times 0.0254 = 0.092 \;\rm m[/tex].
The height if gold bar is, [tex]h = 1.75 \;\rm in =0.044 \;\rm m[/tex].
The density of the gold bar is, [tex]\rho =19,300 \;\rm kg/m^{3}[/tex].
The given problem is based on the concept of density. The density of any substance is equal to the ratio of mass and volume. Considering the gold bar to rectangular shape, the volume of gold bar is calculated as,
[tex]V= L \times w \times h\\\\V = 0.1778 \times 0.092 \times 0.044\\\\V=7.197 \times 10^{-4} \;\rm m^{3}[/tex]
Now, use the formula of density to calculate the mass of gold bar as,
[tex]\rho =\dfrac{m}{V}\\\\m = \rho \times V\\\\m = 19300 \times (7.197 \times 10^{-4})\\\\m= 13.89 \;\rm kg[/tex]
Thus, we can conclude that the mass of such a gold bar is of 13.89 kg.
Learn more about the density of substance here:
https://brainly.com/question/8760548
a burning piece of wood converts ____ energy into ____ energy
Answer:
a burning piece of converts Chemical energy into Heat(Thermal) and Light energy
A box at rest on a ramp at an incline of 22°. The normal force on the box is 538 N
Answer:
F = 580.25 N
Explanation:
It is given that,
A box at rest on a ramp at an incline of 22°
The normal force on the box is 538 N
We need to find the gravitational force on the box.
The force of gravity acting on an object is equal to its weight. So,
F = mg
But here the box is incline at an angle of 22 degrees
It means that mg will resolve in rectangular components such that, normal force is :
[tex]N=mg\cos\theta\\\\mg=F=\dfrac{N}{\cos\theta}\\\\F=\dfrac{538}{\cos22}\\\\F=580.25\ N[/tex]
So, the gravitational force on the box is 580.25 N.
While the block hovers in place, is the density of the block (top left) or the density of the liquid (bottom center) greater?
Answer:
for the body to float, the density of the body must be less than or equal to the density of the liquid.
Explanation:
For a block to float in a liquid, the thrust of the liquid must be greater than or equal to the weight of the block.
Weight is
W = mg
let's use the concept of density
ρ_body = m / V
m = ρ_body V
W = ρ_body V g
The thrust of the body is given by Archimedes' law
B = ρ_liquid g V_liquid
as the body floats the submerged volume of the liquid is less than or equal to the volume of the block
ρ_body V g = ρ_liquid g V_liquid
ρ_body = ρ liquid Vliquido / V_body
As we can see, for the body to float, the density of the body must be less than or equal to the density of the liquid.
A remote-controlled toy car travels at a constant speed of 3 m/s. What distance does the car travel in 6 seconds?
Answer:
speed=d/t.
3=d/6.
d=3×6=18m
The acceleration of an object is always in the direction of the net force acting on it.
Answer:
yes
Explanation:
An object which moves in a circle is accelerating. Accelerations are caused by an unbalanced or net force. The net force is always in the same direction as the acceleration. For objects moving in circles at constant speed, the net force is directed towards the center of the circle about which the object moves.
A cellist tunes the C string of her instrument to a fundamental frequency of 65.4 Hz. The vibrating portion of the string is 0.590 m long and has a mass of 15.0 g.
(a) Calculate the wavelength corresponding to this fundamental frequency?
(b) Calculate the wave speed.
(c) With what tension must the musician stretch the string?
Answer:
a
[tex]\lambda = 1.18 \ m[/tex]
b
[tex]v = 77.172 \ m/s[/tex]
c
[tex]T = 151.41 \ N[/tex]
Explanation:
From the question we are told that
The frequency is [tex]f = 65.4 \ Hz[/tex]
The length of the vibrating string is [tex]L = 0.590 \ m[/tex]
The mass is [tex]m = 15.0 \ g = 0.015 \ kg[/tex]
Generally the wavelength is mathematically represented as
[tex]\lambda = 2 * L[/tex]
=> [tex]\lambda = 2 * 0.590[/tex]
=> [tex]\lambda = 1.18 \ m[/tex]
Generally the wave speed is
[tex]v = \lambda * f[/tex]
=> [tex]v = 1.18 * 65.4[/tex]
=> [tex]v = 77.172 \ m/s[/tex]
Generally the tension on the wire is mathematically represented as
[tex]T = v^2 * \frac{ m }{L }[/tex]
=> [tex]T = 77.172 ^2 * \frac{ 0.015 }{0.590}[/tex]
=> [tex]T = 151.41 \ N[/tex]
: The maximum theoretical efficiency of a Carnot engine operating between reservoirs at the steam point and at room temperature is about A :
Answer:
The value is [tex]\eta = 0.2145[/tex] or 21.45%
Explanation:
From the question we are told that
The first reservoir is at steam point [tex]T_s = 100^o C = 100 + 273 = 373 \ K[/tex]
The second reservoir is at room temperature [tex]T_r = 20^o C = 293 \ K[/tex]
Generally the maximum theoretical efficiency of a Carnot engine is mathematically evaluated as
[tex]\eta = 1- \frac{T_r}{T_s}[/tex]
=> [tex]1 - \frac{ 293}{373}[/tex]
=> [tex]\eta = 0.2145[/tex]
An electron is projected with horizontal speed 105m / s in a downwardly directed 304N / C electric field. Find the vertical position (in m) after 2.0 μs.
Answer:
-107 m
Explanation:
Sum of forces in the y direction:
∑F = ma
-qE = ma
a = -qE/m
a = -(1.60×10⁻¹⁹ C) (304 N/C) / (9.11×10⁻³¹ kg)
a = -53.4×10¹² m/s²
Given in the y direction:
v₀ = 0 m/s
a = -53.4×10¹² m/s²
t = 2×10⁻⁶ s
Find: Δy
Δy = v₀ t + ½ at²
Δy = (0 m/s) (2×10⁻⁶ s) + ½ (-53.4×10¹² m/s²) (2×10⁻⁶ s)²
Δy = -107 m
the kinetic energy of a body executing simple harmonic motion of amplitude A is equal to the potential energy when its displacement is
Answer:
My answer to the question is "when its displacement is zero.
With the LED illuminated, flip the direction of the LED on the breadboard (notch on top now), and then flip it back to its original position (notch on bottom). What does your observation tell you about diodes (and LEDs)?
Explanation:
The full form of LED is Light Emitting Diode. It is a semi conductor source of light which when electrons passes or flows through them, it emits light. In the semi conductor, the electrons recombine with the electron holes to release high amount of energy. This energy is called photon.
When the LED direction is flipped in the breadboard and back to the original position, the LEDs are forced to be grounded. They will not be able to function without being grounded.
A bungee cord stretches 25 meters and has a spring constant of 140 N/m. How much energy is stored in the bungee
Answer:
87.5 kJExplanation:
The potential energy stored in a stretch spring is given by the expression below
PE = Work = force * distance
So:
[tex]PE = (kx) * x[/tex]
This then simplifies to:
[tex]PE = kx^2[/tex]
where k is the spring constant= 140 N/m
Given that x= 25 m
Substituting our data into the expression for P.E stored we have
[tex]PE = 140*25^2\\\\PE= 140*625\\\\PE= 87500 J[/tex]
Hence the energy stored in the spring is 87.5kJ
During the class prize-giving ceremony, Anand clapped his hands hard while Kumar clapped his hands softly. Everybody could hear Anand's clapping while only a few could hear Kumar's clapping. This was because the sound produced by Anand was of____________.
A - higher pitch
B - lower frequency
C - higher volume
D- lower pitch
Answer:
C - higher volume
Explanation:
The pitch or frequency of sound that an object can produce depends upon its size and configuration . The shape of hand of all are same so the frequency of sound produced by hands of all will be almost same . Hence frequency of sound produced by the hands of Anand and Kumar would have been almost the same .
But the intensity of sound produced by them would have been different . Intensity represents energy a sound carries . Hard hitting clap will produce sound of higher intensity . Intensity of sound is also called high volume sound . So Kumar's clap will carry greater energy and hence greater volume of sound .