Answer:
E) the energy stored will quadrupled
Explanation:
The correct question is
A parallel plate capacitor consists of two square parallel plates separated by a distance d. If i double the potential across the plates, while keeping everything else constant, what happens to the energy stored in the capacitor?
A) There will be 1/4 of the energy stored
B) There will be 1/2 of the energy stored
C) The energy stored will remain constant
D) The energy stored will double
E) the energy stored will quadruple
The initial energy stored in the capacitor [tex]E_{i}[/tex] = [tex]\frac{1}{2}CV^{2}[/tex]
where C is the capacitance
V is the potential difference
If I double this voltage, while holding every other parameters constant, the new energy stored will be
[tex]E_{n}[/tex] = [tex]\frac{1}{2}C(2V)^{2}[/tex] = [tex]\frac{4}{2}CV^{2}[/tex]
[tex]E_{n}[/tex] = [tex]2CV^{2}[/tex]
dividing new energy stored by the initial energy stored, we have
[tex]E_{n}/E_{i}[/tex] = [tex]2CV^{2}[/tex] ÷ [tex]\frac{1}{2}CV^{2}[/tex] = 4
the energy stored will be quadrupled.
Hydrogen atom number 1 is known to be in the 4f state. Hydrogen atom number 2 is in the 5d state.
Required:
a. What is the energy of the atom?
b. WHat is the magnitude of this atom's orbital angular momentum?
c. Hydrogen atom number 2 is in the 5d state. Is this atom's energy greater than, less than, or the same as that of atom 1? Explain.
d. Is the magnitude of the orbital angular momentum of atom 1 greater than, less than, or the same as that of atom 2? Explain.
Answer:
4f E₄ = 0.85 eV, L₄ = 4.22 10⁻³⁴ ,
5d E₅ = 0.544 eV , L5 = 5.28 10⁻³⁴
Explanation:
Let's use the Bohr model, stable the energy of the hydrogen atom
E = -13.606 / n2
where Eo = 13.606 eV is the energy of the ground states.
a) the energy of each atom
level 4f
In this nomenclature enumeration is the number n
E = -13606 / 42
E₄ = 0.85 eV
level 5d
E₅ = -13.606 / 5 2
E₅ = 0.544 eV
b) The angular momentum is given in Boh's model
L = n h / 2pi
let's calculate
level 4f L₄ = 4 6.63 10⁻³⁴-34 / 2 pi
L₄ = 4.22 10⁻³⁴
level 4d
L5 = 5 6.63 10-⁻³⁴ / 2pi
L5 = 5.28 10⁻³⁴
c) The hydrogen atom in state n = 5 has lower energy than the other state
d) Atom 1 has less angular momentum than atom 2
Which of the following is an SI unit
Answer:
liter is the SI unit
idk how to explain it
Planet Tatoone is about 1.7 AU from its Sun. Approximately how long will it take for light to travel from the Sun to Tatoone in minutes? Use 3 × 108 m/s for the speed of light.
Answer:
The value is [tex]t = 14.129 \ minutes[/tex]
Explanation:
From the question we are told that
The distance of planet Tatoone is [tex]d = 1.7 \ AU = 1.7 *1.496* 10^{11}=2.543*10^{11} \ m[/tex]
The speed of light is [tex]c = 3.0*10^{8} \ m/ s[/tex]
Generally the time taken is mathematically represented as
[tex]t = \frac{d}{c}[/tex]
=> [tex]t = \frac{2.543*10^{11}}{3.0*10^{8} }[/tex]
=> [tex]t = 847.7 \ s[/tex]
Now converting to minutes
[tex]t = \frac{847.7}{60}[/tex]
=> [tex]t = 14.129 \ minutes[/tex]
These spectra are from the same element. Which is an emission spectrum, which an absorption spectrum?
A. Either could be emission (or absorption), depending on the conditions with which they were made.
B. Top is absorption; bottom emission.
C. Can't tell without knowing the element.
D. Top is emission; bottom absorption.
Answer:
D. Top is emission; bottom absorption.
Explanation:
Emission and spectrum of elements are due to the element absorbing or emitting wavelength of e-m energy. Elementary particles of elements can absorb energy from a ground state to enter an excited state, creating an absorption spectrum, or they can lose energy and fall back to a lower energy state, creating an emission spectrum. A simple rule to differentiate between an emission and an absorption spectrum is that: "all absorbed wavelength is emitted, but not all emitted wavelength is absorbed."
From the image, the lines indicates wavelengths. We can see that all of the wavelengths of the bottom absorption spectrum coincides with some of the wavelength of the upper emission wavelengths.
which formula is used to calculate average velocity?
The answer is:
the first oneThe formula to calculate average velocity is a) V (average ) = x(f) - x(i) /t(f) - t(i)
What is average velocity ?Average velocity is a vector quantity . It is defied as the change in displacement over a time interval .
Average velocity can be calculated as
Average velocity = change in displacement / change in time travel
correct answer is a) V (average ) = x(f) - x(i) /t(f) - t(i)
where
x(f) = final position
x(i) = initial position
t(f) = final time
t(i) = initial time
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Two particles, one with charge −7.97×10−6 C and the other with charge 6.91×10−6 C, are 0.0359 m apart. What is the magnitude of the force that one particle exerts on the other?
Answer:
-384.22N
Explanation:
From Coulomb's law;
F= Kq1q2/r^2
Where;
K= constant of Coulomb's law = 9 ×10^9 Nm^2C-2
q1 and q2 = magnitudes of the both charges
r= distance of separation
F= 9 ×10^9 × −7.97×10^−6 × 6.91×10^−6/(0.0359)^2
F= -495.65 × 10^-3/ 1.29 × 10^-3
F= -384.22N
Physical Science questions that I need HELP ON
Answer:
7a. CO2 => carbon dioxide
b. H2O => water
8. The mass of carbon dioxide, CO2 plus the mass of water, H2O is equal to the mass of sugar, C6H12O6 plus the mass of oxygen, O2.
Explanation:
7. Selecting the names of the reactant.
6CO2 + 6H2O —> C6H12O6 + 6O2
From the above equation, the reactants are: CO2 and H2O
Thus, the names of the reactants are:
a. CO2 => carbon dioxide
b. H2O => water
8. Determination of masses of the CO2, H2O, C6H12O6 and O2 from the balanced equation. This can be obtained as follow:
6CO2 + 6H2O —> C6H12O6 + 6O2
Molar mass of CO2 = 12 + (2x16) = 44 g/mol
Mass of CO2 from the balanced equation = 6 x 44 = 264 g
Molar mass of H2O = (2x1) + 16 = 18 g/mol
Mass of H2O from the balanced equation = 6 x 18 = 108 g
Molar mass of C6H12O6 = (12x6) + (12x1) + (16x6) = 72 + 12 + 96 = 180 g/mol
Mass of C6H12O6 from the balanced equation = 1 x 180 = 180 g
Molar mass of O2 = 16x2 = 32 g/mol
Mass of O2 from the balanced equation = 6 x 32 = 192 g
Summary:
Mass of Reactant:
CO2 = 264 g
H2O = 108 g
Total = 372 g
Mass of Product:
C6H12O6 = 180 g
O2 = 192 g
Total = 372 g
From the above calculations,
The mass of carbon dioxide, CO2 plus the mass of water, H2O is equal to the mass of sugar, C6H12O6 plus the mass of oxygen, O2.
What is your hypothesis regarding difference in urine specific gravity between subjects who drank water and subjects who a drank sports drink
Answer:
Sports drink will show increase in specific gravity
While
Water will decrease in SG
Explanation:
This is because the relative density of urine will increase because of presence of ions in the sport drink unlike in water that has very little ions
Neutrons travelling at 0.400 m/s are directed through a pair of slits having 1.00 m separation. an array of detectors is placed 10.0 m from the slits.
a) What is the de Broglie wavelength of the neutrons?
b) How far off axis if the first zero-intensity point on the detector array?
c) When a neutron reaches a detector, can we say which slit the neutrons passed through? Explain.
Answer:
9.91*10^-7 m
4.955*10^-6 m
Explanation:
Given that
v = 0.4 m/s
d = 1 m
L = 10 m
h = 6.62*10^-34 Js
m(neutron) = 1.67*10^-27 kg
To find the debroglie wavelength of the neutron, we use the formula
λ = h/mv
Now, we plug in the values we have listed.
λ = 6.62*10^-34 / (1.67*10^-27 * 0.4)
λ = 6.62*10^-34 / 6.68*10^-28
λ = 9.91*10^-7 m
b)
y1 = L (m + ½) λ/d, where m = 0
y1 = L (0 + ½) λ/d
y1 = L (½) λ/d
y1 = L/2 * λ/d or
y1 = Lλ/2d
now, we substitute the values for each of them, we have
y1 = (10 * 9.91*10^-7) / (2 * 1)
y1 = 9.91*10^-6 / 2
y1 = 4.955*10^-6 m
c) no, we can not say the neuron passed through one slit
An oceanographer is studying how the ion concentration in seawater depends on depth. She makes a measurement by lowering into the water a pair of concentric metallic cylinders at the end of a cable and taking data to determine the resistance between these electrodes as a function of depth. The water between the two cylinders forms a cylindrical shell of inner radius r_a, outer radius r_b, and length L much larger than r_b. The scientist applies a potential difference Delta V between the inner and outer surfaces, producing an outward radial current I. Let rho represent the resistivity of the water.
(a) Find the resistance of the water between the cylinders in terms of L, rho, r_a, and r_b.
(b) Express the resistivity of the water in terms of the measured quantities L, r_a, r_b, Delta V and I.
Answer:
a) R = ρ₀ L /π(r_b² - R_a²) , b) ρ₀ = V / I π (r_b² - R_a²) / L
Explanation:
a) The resistance of a material is given by
R = ρ l / A
where ρ is the resistivity, l is the length and A is the area
the length is l = L and the resistivity is ρ = ρ₀
the area is the area of the cylindrical shell
A = π r_b² - π r_a²
A = π (r_b² - r_a²)
we substitute
R = ρ₀ L /π(r_b² - R_a²)
b) The potential difference is related to current and resistance by ohm's law
V = i R
we subsist the expression of resistance
V = I ρ₀ L /π (r_b² - R_a²)
ρ₀ = V / I π (r_b² - R_a²) / L
A photographer uses his camera, whose lens has a 50 mm focal length, to focus on an object 1.5 m away. He then wants to take a picture of an object that is 30 cm away.
How far must the lens move to focus on this second object?
Answer:
The distance is [tex]z = 0.008 \ m[/tex]
Explanation:
From the question we are told that
The focal length is [tex]f = 50 \ mm = 50*10^{-3} \ m[/tex]
Generally the lens equation is mathematically represented as
[tex]\frac{1}{u} + \frac{1}{v} = \frac{1}{f}[/tex]
At image distance u = 1.5 m
[tex]\frac{1}{1.5} + \frac{1}{v} = \frac{1}{50 *10^{-3}}[/tex]
=> [tex]\frac{1}{50 *10^{-3}} - \frac{1}{1.5} = \frac{1}{v}[/tex]
=>[tex]v = 0.052 \ m[/tex]
At image distance [tex]u = 30\ cm = 0.30 \ m[/tex]
[tex]\frac{1}{0.3} + \frac{1}{v_1} = \frac{1}{50 *10^{-3}}[/tex]
=> [tex]\frac{1}{50 *10^{-3}} - \frac{1}{0.30 } = \frac{1}{v_1}[/tex]
=> [tex]v_1 = 0.06 \ m[/tex]
The distance the lens need to move is evaluate as
[tex]z = |v - v_1|[/tex]
[tex]z = |0.052 - 0.06|[/tex]
[tex]z = 0.009 \ m[/tex]
An electron from a Ti ^ + 2 hydrogen ion leaps from one orbit with radius 13.25 angstrom to another orbit with radius 2.12 angstrom. determine the energy (Joule) e produced in said transition and the wavelength (in cm)
Answer:
E = 0.2276 10⁻¹⁹ J , λ = 8.73374 10⁻⁴ cm
Explanation:
Bohr's atomic model can be used for hydrogen-type atoms, that is, they have a single electron in their last orbit, this is the case of doubly ionized Titanium.
It is much easier to work in EV units.
r = a₀ / Z n²
E = - 13.606 (Z² / n²)
where ao is the Bohr radius, which is the ground state orbital of hydrogen a₀ = 0.0529 nm, Z is the atomic number of titanium, and n is an integer that represents the different states of the system.
a) Let's look for the energy, for this we look for the integer numbers of these orbits
r = 13.25 A = 1.325 nm
r = a₀ / Z n²
n = √(Z r / a₀)
the atomic number of titanium is Z = 22
n = √ (22 1.325 / 0.0529)
n = 23
r = 2.12 A = 0.212 nm
n = √ (22 0.212 / 0.0529)
n = 9
now we can calculate the energy of the transition
E = 13.606 (1 / [tex]n_{f}^2[/tex] - 1 / [tex]x_{o}^2[/tex])
E = 13.606 (1/9² - 1/23²)
E = 13.6060 (0.010455)
E = 0.1423 eV
Let's reduce to J
E = 0.1423 eV (1.6 10⁻¹⁹ J / 1eV) = 0.2276 10⁻¹⁹ J
To find the wavelength of the transition, use the Planck relation
E = h f
the relationship of frequency and speed of light
c = λ f
we substitute
E = h c /λ
λ = hc / E
λ = 6.626 10⁻³⁴ 3 10⁸ / 0.2276 10⁻¹⁹
λ = 8.73374 10⁻⁶ m
λ = 8.73374 10⁻⁴ cm
Scientists pose a ___ to examine cause and effect relationships.
Answer:
hypothesis
Explanation:
I think this is right I dont remember
Mention four importance of writing the physical quantities as vectors.
Answer:
Explanation:
Knowledge of vectors is important because many quantities used in physics are vectors. If you try to add together vector quantities without taking into account their direction you'll get results that are incorrect.
Some of the key vector quantities in physics: force, displacement, velocity, and acceleration.
An example of the importance of vector addition could be the following:
Two cars are involved in a collision. At the time of the collision car A was travelling at 40 mph, car B was travelling at 60 mph. Until I tell you in which directions the cars were travelling you don't know how serious the collision was.
The cars could have been travelling in the same direction, in which case car B crashed into the back of car A, and the relative velocity between them was 20 mph. Or the cars could have been travelling in opposite directions, in which case it was a head on collision with a relative velocity between the cars of 100 mph!
Vector is defined as a quantity having direction as well as magnitude, especially as determining the position of one point in space relative to another
What is vector quantity?Vector is defined as a quantity having direction as well as magnitude, especially as determining the position of one point in space relative to another
Knowledge of vectors is important because many quantities used in physics are vectors. If you try to add together vector quantities without taking into account their direction you'll get results that are incorrect.
Some of the key vector quantities in physics: force, displacement, velocity, and acceleration.
An example of the importance of vector addition could be the following:
Two cars are involved in a collision. At the time of the collision car A was travelling at 40 mph, car B was travelling at 60 mph. Until I tell you in which directions the cars were travelling you don't know how serious the collision was.
The cars could have been travelling in the same direction, in which case car B crashed into the back of car A, and the relative velocity between them was 20 mph. Or the cars could have been travelling in opposite directions, in which case it was a head on collision with a relative velocity between the cars of 100 mph!
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a pistol fires a bullet towards a target located 175m away. The bullet is traveling at 320 m/s. How long does it take for the bullet to hit the target?
Time = distance/speed
Time = (175 m) / (320 m/s)
Time = 0.547 second
What is the difference between
Dobereiner's triads and Newland's octaves
Answer:
Newlands law of octave was the first logically basis on the atomic weight. Demerits of dobereiner's triads system: - This system fails because it does not hold good for all the elements discovered till date time. It is limited to only few elements.
Explanation:
difference between far point and near point
Answer:
Far point = is the farthest point where you can see the object
near point= is the nearest distance where you can see the object.
Explanation:
The far point of human eye is upto infinity & the near point is 25cm.
One train is at the 20 Km position, another is at the 200Km position, both are approaching, the first with a speed of 30Kmh-1 and the second with a speed of 48 Kmh-1. If they leave at 7:12, what time do they cross? Answer: t = 2.30 H Time: 9:30 am.
Explanation:
The distance between them is 200 km − 20 km = 180 km.
The relative velocity is 30 km/h − (-48 km/h) = 78 km/h.
The time it takes is 180 km / (78 km/h) = 2.31 hours, or 2 hrs 18 min.
Therefore, the trains meet at 9:30 AM.
An astronaut in an inertial reference frame measures a time interval Δt between her heartbeats. What will observers in all other inertial reference fr
Answer:
It will be more than deta t
Explanation:
Because
deta t' = န deta t
But န= 1/√ (1 - v²/c²
So the observers in all the initial frames will be more than deta t
Goslo and Speedo are twins. They have just celebrated their 20th birthday (Yay!). Speedo travels to the planet Zorth which is 40 light years away, he immediately returns. Neglect any time Speedo spent accelerating. If Speedo travels at 0.997 relative to the Earth, who will measure the proper time?
a. Goslo
b. Speedo
c. Nobody
d. Everybody
Answer:
a. Goslo
Explanation:
given data
Speedo travels = 40 light year
Speedo travels relative to the Earth = 0.997
solution
Goslo will measure here proper time and this time is expres as
time T = Speedo travels ÷ Speedo travels relative to the Earth ..........................1
put here value
time T = [tex]\frac{40}{0.997}[/tex]
time T = 40.1 year
so Goslo will measure the proper time
A westward-moving bicycle increased its speed from 2.0m/s to 12.0m/s in 4.0 seconds. What is the magnitude and direction of the acceleration?
Answer:
2.5 m/s^2
Explanation:
Acceleration = (Final Velocity - Initial Velocity) / TIme
Acceleration = 12 - 2 / 4
=> Acceleration = 10 /4
=> Accelration = 5/2
=> Acceleration = 2.5 m/s^2
So, Acceleration is 2.5 m/s^2
The acceleration of the bicycle which is the change in the velocity of the bike with change in time will be 2.5m/s in the Westward direction
Initial speed = 2.0 m/s Final speed = 12.0 m/s Change in time, △t = 4.0 secondsWe define acceleration thus :
Acceleration = (△velocity / △time) Change in velocity = (12 - 2) = 10 m/s Acceleration = 10 / 4 = 2.5 m/s²Therefore, the acceleration of the bike will be 2.5m/s² in the West direction
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The potential energy U of an object of mass m that is separated by a distance R from an object of mass M is given by U= -GMm/RA. What is the kinetic energy K of the satellite?Express your answer in terms of the potential energy .
B. Find an expression for the square of the orbital period.
Answer:
A) K = ½ U / r , B) T² = (4π² / G M) r³
Explanation:
A) It asks us for the kinetic energy of the satellite and they give us the relation of the potential synergy
U = - G M m / r
the force can be found from this expression
F = - dU / dr
F = - G M m / r²
The kinetic energy is given by the formula
K = ½ m v²
let's use Newton's second law
F = m a
G M m / r² = m a
where the acceleration is centripetal
a = v² / r
G M r² = v² / r
v² = G M r³
we substitute the expression for the kinetic energy
K = ½ m v²
K = ½ m G M r³
in terms of potential energy is
K = ½ (G M m r²) 1 / r
K = ½ U / r
B) The period of the orbit
We write Newton's second law
G M m / r² = m a
a = v² / r
in a circular orbit the speed of the velocity is constant
v = d / t
the longitude of the orbit is
d = 2π r
v = 2π r / T
we substitute
G Mm / r² = m (2πr / T)² / r
G M / r³ = 4π² / T²
T² = (4π² / G M) r³
(A) The kinetic energy of satellite in terms of potential energy is,
K = 1/2 U / R.
(B) The expression for the square of the orbital period is,
T² = (4π² / G M) R³
Given data:
The potential energy of object is, U.
The mass of object is, m.
The distance from the other object of mass M is, R.
A.
The kinetic energy of the satellite and they give us the relation of the potential synergy,
U = - G M m / R
And the force can be found from this expression
F = - dU / dR
F = - G M m / R²
The kinetic energy is given by the formula
K = 1/2 m v²
Now use Newton's second law
F = m a
G M m / R² = m a
where the acceleration is centripetal
a = v² / R
G M R² = v² / R
v² = G M R³
we substitute the expression for the kinetic energy
K = 1/2 m v²
K = 1/2 m G M R³
in terms of potential energy is
K = 1/2 (G M m R²) 1 / R
K = 1/2 U / R
Thus, we can conclude that the kinetic energy of satellite in terms of potential energy is K = 1/2 U / R.
(B)
Now we need to obtain the period of the orbit of satellite. For that we write Newton's second law as
G M m / r² = m a
Since,
a = v² / r
In a circular orbit the speed is constant,
v = d / t
For the longitude of the orbit is
d = 2π R
v = 2π R / T
here,
T is the orbital period of satellite.
Substituting the values as,
G Mm / R² = m (2πR / T)² / R
G M / R³ = 4π² / T²
T² = (4π² / G M) R³
Thus, we can conclude that the expression for the square of the orbital period is T² = (4π² / G M) R³.
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A rectangular trough, 1.6 m long, 0.60 m wide, and 0.35 m deep, is completely full of water. One end of the trough has a small drain plug right at the bottom edge.
When you pull the plug, at what speed does water emerge from the hole?
Answer:
v = 2.61 m/s
Explanation:
Given that,
Length of a rectangular trough, l = 1.6 m
Breadth of a rectangular trough, b = 0.6 m
Depth of a rectangular trough, h = 0.35 m
We need to find the speed with which water emerge from the hole. It is a concept of efflux. The velocity of efflux is given by :
[tex]v=\sqrt{2gh}\\\\v=\sqrt{2\times 9.8\times 0.35}\\\\v=2.61\ m/s[/tex]
So, water will emerge from the hole with a speed of 2.61 m/s.
A cheetah can accelerate from rest to 25.0 m/s in 6.22 s. What is the cheetah's average speed for the first 3.11 s of its sprint
Answer:
18.75m/sExplanation:
Given data
initial speed ,u= o m/s
final speed v= 25 m/s
time t= 3.11 seconds
Applying the first equation of motion we have
[tex]v= u+at\\\\v-u=at\\\\a= \frac{v-u}{t} \\\\a= \frac{25-0}{6.22} \\\\a= 4.02 m/s^2[/tex]
Also applying [tex]v=u+at[/tex] with initial speed set at 0, we can also find speed at 3.11 seconds
[tex]v=0+4.02*3.11\\v= 12.50 m/s[/tex]
Hence the average speed in the first 3.11 seconds is
[tex]\bar v= \frac{v}{2} \\\\\bar v=\frac{ 12.50}{2} \\\\ \bar v= 6.25 m/s[/tex]
Applying the expression [tex]\bar v=\bar u+at[/tex] we can now fing the average speed in the second 3.11 second
[tex]\bar v=\bar u+at\\\\ \bar v=6.25+4.02*3.11\\\\ \bar v=18.75m/s[/tex]
What is the difference between 103.5 and 102.24 written with the correct number of significant figures?What is the difference between 103.5 and 102.24 written with the correct number of significant figures?
Answer:
1.260
Explanation:
103.5 has 4 significant figures.
102.24 has 5 significant figures.
We will need to round the answer to the least number of significant figures available (in this case, 4).
103.5 − 102.24 = 1.26 = 1.260
The difference between 103.5 and 102.24 is equal to 1.3 in the correct number of significant figures.
What are significant figures?Significant figures can be utilized to produce numbers that can be written in the form of figures. We can determine the number of significant figures by simply counting the values starting from the first non-zero digit placed on the left.
We can calculate the number of significant digits by counting from the first non-zero figure placed on the left. The significant digits of a given number are those significant digits, which convey the meaning with respect to its accuracy.
In the case of division or multiplication or subtraction and addition, the number of significant figures must be the same as the value with the fewest significant figures.
We have to find the difference between 103.5 and 102.24:
103.5 - 102.24 = 1.26 = 1.3
The number 103.5 has one significant figure after the decimal. Therefore, the answer will be equal to 1.3.
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An object has a height of 0.066 m and is held 0.210 m in front of a converging lens with a focal length of 0.140 m. (Include the sign of the value in your answers.)
(a) What is the magnification?
(b) What is the image height?
m
Explanation:
Given that,
Size of object, h = 0.066 m
Object distance from the lens, u = 0.210 m (negative)
Focal length of the converging lens, f = 0.14 m
If v is the image distance from the lens, we can find it using lens formula as follows :
[tex]\dfrac{1}{v}-\dfrac{1}{u}=\dfrac{1}{f}\\\\\dfrac{1}{v}=\dfrac{1}{f}+\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{0.14 }+\dfrac{1}{(-0.21)}\\\\v=0.42\ m[/tex]
(a) Magnification,
[tex]m=\dfrac{v}{u}\\\\m=\dfrac{0.42}{(-0.21)}\\\\m=-2[/tex]
(b) Magnification, [tex]m=\dfrac{h'}{h}[/tex]
h' is image height
[tex]-2=\dfrac{h'}{0.066}\\\\h'=-2\times 0.066\\\\h'=-0.132\ m[/tex]
Hence, this is the required solution.
Two long wires hang vertically. Wire 1 carries an upward current of 1.20 A. Wire 2, 20.0 cm to the right of wire 1, carries a downward current of 4.20 A. A third wire, wire 3, is to be hung vertically and located such that when it carries a certain current, each wire experiences no net force.
(a) Is this situation possible?
A. Yes
B. No
Is it possible in more than one way?
A. Yes
B. No
(b) Describe the position of wire 3.
distance ________ cm
direction: left of wire 1
(c) Describe the magnitude and direction of the current in wire 3.
magnitude
direction
down
Answer:
a) NO, YES that cable 3 should be placed to the left of cable 1
b) a = 8cm the current is UP
Explanation:
The force between two cables that carries a current is given through the magnetic field created between them, it has the expression
F₁ = μ₀ I₁ I₂ / 2π a l
where I₁ and I₂ are the current in each wire, at the separation between them and l the length of wire 1 on which the force is applied.
The direction of the force this given is given by the vector product between the current in wire 1 and the field created by 2, but we can summarize it:
* if the two currents are in the same direction the force is attractive
* if the two currents are contrary, the force is repulsive
With these relationships we can examine the different situations presented
a) Between cable 1 and 3 the force is zero. If cable 1 the current is upward in cable 3 it must be downward, so that the force is repulsive
Between wire 2 and 3. If wire 2 the current is downward, in wire 3 the current must be upward, for a repulsive force.
We see that in the two conditions the current in cable 3 has different directions, which is impossible, therefore this situation cannot occur
the answer is NO
The only way this is possible is that cable 3 should be placed to the left of cable 1
Answer YES
b) and c) Your question is unclear, I interpret that you want the position of cable 3 so that the force is zero on cable 3
we will assume that the current in cables 1 and 2 is ascending and that in cable 3 is descending
We write Newton's second law at the point of cable 3, the acceleration is zero
F13 - F23 = 0
F13 = F23
Let's calculate the forces
F₁₃ = μ₀ I₁ I₃ /2π a l
F₂₃ = μ₀ I₂ I₃ /2π (d + a) l
we substitute and simplify
I₁ / a = I₂ / (d + a)
where we have assumed that the length of all cables is the same
We solve to find
I₁ (d + a) = I₂ a
a (I₂ - I₁) = I₁ d₁
a = I₁ / (I₂ - I₁) d
let's calculate
a = 1.20 / (4.2 -1.2) 20
a = 8cm
to the left of wire 1 and the direction is the current is UP
so that it is an attractive force between 1 and 3 and a repulsive force between 2 and 3
Which of these forces help protons and neutrons to stay at the center of the Atom
It is found that an engine rejects 100.0 J while absorbing 125.0 J each cycle of operation.
(a) What is the efficiency of the engine?
(b) How much work does it perform per cycle?
Consider a conducting rod of length 34 cm moving along a pair of rails, and a magnetic field pointing perpendicular to the plane of the rails.
Required:
At what speed (in m/s) must the sliding rod move to produce an emf of 0.75V in a 1.75T field?
Answer:
v = 1.26 m/s
Explanation:
Given that,
Length of the conducting rods = 34 cm = 0.34 m
Magnetic field, B = 1.75 T
Induced emf is 0.75 V
we need to find the speed with which it slides. Due to the motion of the rod an emf is induced in it which is given by :
[tex]\epsilon=Blv[/tex]
v is the speed of rod
[tex]v=\dfrac{\epsilon}{Bl}\\\\v=\dfrac{0.75}{1.75\times 0.34}\\\\v=1.26\ m/s[/tex]
So, the speed of the sliding rod is 1.26 m/s.