Answer:
The angle between the polarizing axes of the two polarizers is 54°
Explanation:
Given;
intensity of unpolarized light, I₀ = 54.0 W/m²
intensity of light that emerges from second ideal polarizer, I₁ = 19.0 W/m²
The angle between the polarizing axes of the two polarizers is dtermined by applying Malus' law for intensity of a linearly polarized light passing through a polarizer.
I₁ = I₀Cos²θ
Cos²θ = I₁ / I₀
Cos²θ = 19 / 54
Cos²θ =0.3519
Cos θ = √0.3519
Cos θ = 0.5932
θ = Cos⁻¹(0.5932)
θ = 53.6°
θ = 54°
Therefore, the angle between the polarizing axes of the two polarizers is 54°
Comparing helium atoms with nitrogen molecules at the same temperature, the helium atoms on average are moving _______ and have _______ kinetic energy.
Answer:
Helium atoms compared to nitrogen atoms are moving faster and have a greater kinetic energy.
Explanation:
The molecular velocity of a gas at room temperature is inverse proportional to the square root of its molecular mass.
The greater the molecular mass of the gas the lesser the average speed of its molecules. Comparing the molecular masses of nitrogen and helium, helium is found to have a lower molecular mass and a corresponding greater velocity.
Hence helium moves faster than nitrogen and has a higher kinetic energy than nitrogen
The process of star and planet formation begins with a large cloud of gas and dust called a solar nebula. Rank the formation events that occur within a cloud from earliest to latest.
Rank from earliest to latest. To rank items as equivalent, overlap them.
A. The cloud is large, cool, and slowly rotating
B. The cloud collapses into a disk
C. Competing rotational and gravitational forces begin to flatten the cloud
D. The cloud becomes denser, heats up, and rotates faster
E. The cloud starts to contract under the influence of gravity
A, B, E , C, D
What is Nebula?A nebula is an enormous cloud of dust and gas occupying the space between stars and acting as a nursery for new stars.
Nebulae are made up of dust, basic elements such as hydrogen and other ionized gases.
Nebula Formation:
In essence, a nebula is formed when portions of the interstellar medium undergo gravitational collapse.
Mutual gravitational attraction causes matter to clump together, forming regions of greater and greater density.
The formation events that occur within a cloud from earliest to latest are:
A. The cloud is large, cool, and slowly rotating
B. The cloud collapses into a disk.
E. The cloud starts to contract under the influence of gravity
C. Competing rotational and gravitational forces begin to flatten the cloud.
D. The cloud becomes denser, heats up, and rotates faster
Therefore , The rank from earliest to latest is A, B, E , C, D
Learn more about Nebula here:https://brainly.com/question/9497068
#SPJ2
An astronomy student, for her PhD, really needs to estimate the age of a cluster of stars. Which of the following would be part of the process she would follow?
A. plot an H-R diagram for the stars in the cluster
B. count the number of M type stars in the cluster
C. measure the Doppler shift of a number of the stars in the cluster
D. search for planets like Jupiter around the stars in the center of the cluster
E. search for x-rays coming from the center of the cluster
Answer:
A. plot an H-R diagram for the stars in the cluster.
Explanation:
A star cluster can be defined as a constellation of stars, due to gravitational force, which has the same origin.
The astronomy student would have to plot an H-R diagram for the stars in the cluster and determine the age of the cluster by observing the turn-off point. The turn-off is majorly as a result of gradual depletion of the source of energy of the star. Thus, it projects off the constellation.
An air conditioner connected to a 103 V rms AC line is equivalent to a 20 resistance and a 1.68 inductive reactance in series. a) What is the impedance of the air conditioner
Answer:
20.07ohms
Explanation:
Impedance is defined as the opposition to the flow of current through the elements of the circuit.
Impedance for R-L AC circuit is expressed as Z = √R²+XL²
R is the resistance
XL is the inductive reactance.
Given resistance of the air condition = 20 ohms
Inductive reactance XL = 1.68 ohms
Z = √20²+1.68²
Z = √400+2.8224
Z = √402.8224
Z = 20.07 ohms
Hence the impedance of the air conditioner is 20.07ohms
what effect does condensation on a glass of ice water have on the rate at which the ice melts? Will the condensation speed up the melting process or slow it down?
Answer:
Explanation:
When water droplet condenses on the outer wall of glass of ice , it releases heat equal to mass x latent heat of condensation of water . This heat reaches the ice melting inside glass . Due to this heat , the melting process is accelerated .
Hence the process of melting gets accelerated when water droplet condenses on the outer wall of glass containing mixture of ice and water .
A sailor strikes the side of his ship just below the surface of the sea. He hears the echo of the wave reflected from the ocean floor directly below 2.5 ss later.
How deep is the ocean at this point? (Note: Use the bulk modulus method to determine the speed of sound in this fluid, rather than using a tabluated value.)
_____ m
Answer:
1248m
The time that wave moves from the wave source to the ocean floor is half the total travel time: t = 2.5/2 = 1.25s
The speed of sound in seawater is 1560 m/s
Therefore, s = vt = (1560 m/s)(1.25s) =1248 m = 1.2km
"A power of 200 kW is delivered by power lines with 48,000 V difference between them. Calculate the current, in amps, in these lines."
Answer:
9.6×10⁹ A
Explanation:
From the question above,
P = VI.................... Equation 1
Where P = Electric power, V = Voltage, I = current.
make I the subject of the equation
I = P/V............. Equation 2
Given: P = 200 kW = 200×10³ W, V = 48000 V.
Substitute these vales into equation 2
I = 200×10³×48000
I = 9.6×10⁹ A.
Hence the current in the line is 9.6×10⁹ A.
An electromagnetic ware has a maximum magnetic field strength of 10^-8 T at a specific place in vacuum. What is the intensity of the light at that place. μ0=4πx10^-7 WbA/m g
Answer:
[tex]I=1.19\times 10^{-2}\ W/m^2[/tex]
Explanation:
It is given that,
Maximum value of magnetic field strength, [tex]B=10^{-8}\ T[/tex]
We need to find the intensity of the light at that place.
The formula of the intensity of magnetic field is given by :
[tex]I=\dfrac{c}{2\mu _o}B^2[/tex]
c is speed of light
So,
[tex]I=\dfrac{3\times 10^8}{2\times 4\pi \times 10^{-7}}\times (10^{-8})^2\\\\I=1.19\times 10^{-2}\ W/m^2[/tex]
So, the intensity of the light is [tex]1.19\times 10^{-2}\ W/m^2[/tex].
Two parallel plates have charges of equal magnitude but opposite sign. What change could be made to increase the strength of the electric field between the plates
Answer:
The electric field strength between the plates can be increased by decreasing the length of each side of the plates.
Explanation:
The electric field strength is given by;
[tex]E = \frac{V}{d}[/tex]
where;
V is the electric potential of the two opposite charges
d is the distance between the two parallel plates
[tex]E =\frac{V}{d} = \frac{\sigma}{\epsilon _o} \\\\(\sigma = \frac{Q}{A} )\\\\E = \frac{Q}{A\epsilon_o} \\\\E = \frac{Q}{L^2\epsilon_o}[/tex]
Where;
ε₀ is permittivity of free space
L is the length of each side of the plates
From the equation above, the electric field strength can be increased by decreasing the length of each side of the plates.
Therefore, decreasing the length of each side of the plates, could be made to increase the strength of the electric field between the plates
A child pulls on a wagon with a force of 75 N. If the wagon moves a total of 42 m in 3.1 min, what is the average power delivered by the child
Answer:
16.96 W
Explanation:
Power: This can be defined as the rate at which work is done by an object. The S.I unit of power is Watt(W).
From the question,
P = (F×d)/t....................... Equation 1
Where P = power, F = force, d = distance, t = time.
Given: F = 75 N, d = 42 m, t = 3.1 min = 3.1×60 = 186 s
Substitute these values into equation 1
P = (75×42)/186
P = 16.94 W
Hence the average power delivered by the child = 16.96 W
The average power delivered by the child is 16.96 W.
What is Power?Power can be defined as the rate at which work is done by an object. The S.I unit of power is Watt(W).
Work done is the product of force and displacement caused.
Then the formula of power will be
P = (F×d)/t
Substitute F = 75 N, d = 42 m, t = 3.1 min = 3.1×60 = 186 s, we get the power as
P = (75×42)/186
P = 16.94 W
Hence, the average power delivered by the child is 16.96 W.
Learn more about power.
https://brainly.com/question/15120631
#SPJ5
What are the approximate dimensions of the smallest object on Earth that astronauts can resolve by eye when they are orbiting 275 km above the Earth
Answer:
s_400 = 16.5 m , s_700 = 29.4 m
Explanation:
The limit of the human eye's solution is determined by the diffraction limit that is given by the expression
θ = 1.22 λ / D
where you lick the wavelength and D the mediator of the circular aperture.
In our case, the dilated pupil has a diameter of approximately 8 mm = 8 10-3 m and the eye responds to a wavelength between 400 nm and 700 nm.
by introducing these values into the formula
λ = 400 nm θ = 1.22 400 10⁻⁹ / 8 10⁻³ = 6 10⁻⁵ rad
λ = 700 nm θ = 1.22 700 10⁻⁹ / 8 10⁻³-3 = 1.07 10⁻⁴ rad
Now we can use the definition radians
θ= s / R
where s is the supported arc and R is the radius. Let's find the sarcos for each case
λ = 400 nm s_400 = θ R
S_400 = 6 10⁻⁵ 275 10³
s_400 = 16.5 m
λ = 700 nm s_ 700 = 1.07 10⁻⁴ 275 10³
s_700 = 29.4 m
Two small plastic spheres are given positive electrical charges. When they are 20.0 cm apart, the repulsive force between them has magnitude 0.200 N.
1. What is the charge on each sphere if the two charges are equal? (C)
2. What is the charge on each sphere if one sphere has four times the charge of the other? (C)
Answer:
A. 2.97x 10^-6C
B. 1.48x10^ -6 C
Explanation:
Pls see attached file
Answer:
1) +9.4 x 10^-7 C
2) +4.72 x 10^-7 C and +1.9 x 10^-6 C
Explanation:
The two positive charges will repel each other
Repulsive force on charges = 0.200 N
distance apart = 20.0 cm = 0.2 m
charge on each sphere = ?
Electrical force on charged spheres at a distance is given as
F = [tex]\frac{kQq}{r^{2} }[/tex]
where F is the force on the spheres
k is the Coulomb's constant = 8.98 x 10^9 kg⋅m³⋅s⁻²⋅C⁻²
Q is the charge on of the spheres
q is the charge on the other sphere
r is their distance apart
since the charges are equal, i.e Q = q, the equation becomes
F = [tex]\frac{kQ^{2} }{r^{2} }[/tex]
making Q the subject of the formula
==> Q = [tex]\sqrt{\frac{Fr^{2} }{k} }[/tex]
imputing values into the equation, we have
Q = [tex]\sqrt{\frac{0.2*0.2^{2} }{8.98*10^{9} } }[/tex] = +9.4 x 10^-7 C
If one charge has four times the charge on the other, then
charge on one sphere = q
charge on the other sphere = 4q
product of both charges = [tex]4q^{2}[/tex]
we then have
F = [tex]\frac{4kq^{2} }{r^{2} }[/tex]
making q the subject of the formula
==> q = [tex]\sqrt{\frac{Fr^{2} }{4k} }[/tex]
imputing values into the equation, we have
q = [tex]\sqrt{\frac{0.2*0.2^{2} }{4*8.98*10^{9} } }[/tex] = +4.72 x 10^-7 C
charge on other sphere = 4q = 4 x 4.72 x 10^-7 = +1.9 x 10^-6 C
Find the total energy (ft-lb) of an aircraft weighing 20,000 lbs at 5,000 ft true altitude and 200 KTS true air speed. Group of answer choices
Answer:
Hello the options to your question is missing below are the options
2 x 10^8 ft-lb
15527950 ft-lb
2.8 x 10^7 ft-lb
13.55 x 10^7 ft-lb
Answer : 13.55 * 10^7 ft-Ib
Explanation:
Given data :
weight of Aircraft (p) = 20000 Ibs
height ( h ) = 5000 ft
Velocity = 200 KTS = 370 km/h ( 10277 m/s) where 1 KTS = 1185 km/h
calculate the total energy
Total energy = potential energy + kinetic energy
potential energy = mgh = p * h =20000 * 5000 = 100 * 10^6 ft-Ibs
kinetic energy = 1/2 mv^2 = 1/2 * 625 * (33709)^2 = 3551 *10^6 ft-Ibs
where ; m = p/g = 20000 / 32 = 625 Ibs
v = 10277 m/s ≈ 33709 ft/s
hence total energy = 100 * 10^6 + 3551 * 10^6 = 1355*10^7 ft-Ibs
6) Set the battery to a value between 0.0 V and 1.5 V. Now drag the voltage meter toward the capacitor and move the red and black leads to measure the voltage. Determine the potential difference between the two plates and whether the top plate is at higher or lower voltage than the bottom plate.
Answer:
A) 1.5 v
B) Top plate is at higher voltage than the bottom plate
Explanation:
Battery value set between 0.0 V and 1.5 V
a) The potential difference between the plates
Δ V = V1( potential at top plate) - V2( potential at lower plate )
potential at top plate = 1.5 V
potential at lower plate = 0.0 V
hence potential difference = 1.5 V
b ) The top plate is always connected to the positive terminal of the DC source ( which is at a higher potential )while the bottom plate is connected to the negative terminal of the DC source ( which is at a lower potential )
hence the Top plate is at higher voltage than the bottom plate
For a particle executing SHM with an amplitude ‘r’, the kinetic energy will be equal to the potential energy when the displacement is equal to-
Answer:
x = A sin w t displacement in SHM
v = A w cos w t velocity in SHM
PE = 1/2 k x^2 = 1/2 k A^2 sin^2 w t
KE = 1/2 m v^2 = 1/2 m w^2 A^2 cos^2 w t
If KE = PE then
k sin^2 w t = m w^2 cos^2 w t
sin^2 wt / cos^2 w t = tan^2 w t = m w^2 / k
but k / m = w^2
So tan^2 w t = 1 and tan w t = 1 or w t = pi / 4 or theta = 45 deg
Then x = r sin w t = r sin 45 = .707 r
a box container both cube and five side pyramid the total number of objects is 17 the total number of side for the cube and pyramid is 95 how many cubes are in the box
Answer:
There are 10 cubes in the box
Explanation:
Let the total number of cubes be x and the total number of pyramids be y
Since there are 17 total objects;
Then;
x + y = 17 •••••••••(i)
Also, the total number of sides of cubes is 6 * x = 6x ( a single cube has 6 sides)
For the pyramid we have 5 * y = 5y
adding both gives the total number of sides
6x + 5y = 95 •••••• (ii)
From i, we cabs say y = 17-x
plug this in ii
6x + 5(17-x) = 95
6x + 85 -5x = 95
6x-5x = 95-85
x = 10
A 68.5kg astronaut floating motionless next to the space station throws a 2.25kg tool away from her at 3.20m/s. With what speed and direction will the astronaut begin to move?
Answer:
-0.105 m/s
Explanation:
Given that
Mass of the astronaut, m(a) = 68.5 kg
Mass of the tool, m(t) = 2.25 kg
Speed of the tool after it is thrown, v(t) = 3.20 m/s
We know that momentum of a particle,
p = mv
See the attachment for calculations
Therefore, the speed is 0.105 m/s and it moves in the opposite direction.
If the direction of the position is north and the direction of the velocity is up, then what is the direction of the angular momentum
Answer:
the direction of angular momentum = EAST
Explanation:
given
Direction of position = r = north
Direction of velocity = v = up
angular momentum = L = m(r x v)
where m is the mass, r is the radius, v is the velocity
utilizing the right hand rule, the right finger heading towards the course of position vector and curl them toward direction of velocity, at that point stretch thumb will show the bearing of the angular momentum.
then L = north x up = East
A 23.3-kg mass is attached to one end of a horizontal spring, with the other end of the spring fixed to a wall. The mass is pulled away from the equilibrium position (x = 0) a distance of 17.5 cm and released. It then oscillates in simple harmonic motion with a frequency of 8.38 Hz. At what position, measured from the equilibrium position, is the mass 2.50 seconds after it is released?
a) 5.23 cm
b) 16.6 cm
c) 5.41 cm
d) 8.84 cm
e) 11.6 cm
Answer:
Option b: 16.6 cm.
Explanation:
The position of the mass at 2.50 s can be found using the simple harmonic motion equation:
[tex] x_{t} = Acos(\omega t) [/tex]
Where:
A: is the amplitude = 17.5 cm
ω: is the angular frequency = 2πf
t = 2.50 s
[tex] x_{t} = Acos(\omega t) = 17.5cos(2\pi*8.38*2.50) = 16.6 cm [/tex]
Therefore, the correct answer is option b: 16.6 cm.
I hope it helps you!
A car starts from rest and accelerates at a constant rate after the car has gone 50 m it has a speed of 21 m/s what is the acceleration of the car
Answer:
4.41 m/s^2
Explanation:
(v_f)^2 - (v_i)^2 = 2a * change in distance
(21)^2 - (0)^2 = 2a * 50
a = (21^2)/(2*50)
a = 4.41 m/s^2
In a single-slit diffraction experiment, the width of the slit through which light passes is reduced. What happens to the width of the central bright fringe
Answer:
It becomes wider
Explanation:
Because The bigger the object the wave interacts with, the more spread there is in the interference pattern. Decreasing the size of the opening increases the spread in the pattern.
When the magnet falls toward the copper block, the changing flux in the copper creates eddy currents that oppose the change in flux. The resulting braking force between the magnet and the copper block always opposes the motion of the magnet, slowing it as it falls. The rate of the fall produces a rate of flux change sufficient to produce a current that provides the braking force. If the copper is cooled with liquid nitrogen, the resistivity of the copper drops dramatically. How will this affect the speed at which the magnet falls toward the copper
Answer:
The speed at which the magnet falls through the copper block will be reduced dramatically.
Explanation:
Eddy's current are loops of electrical current induced within conductors by a changing magnetic field in the conductor. Eddy's current is proportional to the the magnetic field strength, the rate of change of flux, the area of the loop, and is inversely proportional to the resistivity of the material. Eddy currents flows perpendicularly to the magnetic field, and in closed loops within conductors.
Reducing the resistivity of the copper will increase the Eddy current on the copper, which will in turn increase the opposition to the action producing the flux change (the falling magnet through the copper block). The result is that the speed at which the magnet falls through the copper block will be reduced dramatically.
An electron, moving toward the west, enters a uniform magnetic field. Because of this field the electron curves upward. The direction of the magnetic field is
Answer:
The magnetic field's direction is towards the north
Explanation:
The force on a positive charge in a uniform magnetic field is represented by the right hand rule. To determine the direction of the force, place your right hand with your palm up, and your thumb at 90° to the other fingers. If the fingers represent the magnetic field, and the thumb the direction of the positive charge, then the palm will push up in the direction of the force. But a negative charge like an electron pushes in exactly the opposite direction. So if you follow this rule, you will find that the magnetic field points towards the north.
The direction of the magnetic field is towards the North. This can be
determined using the right hand rule by Fleming.
The right hand rule states that to determine the direction of the magnetic
force, the right thumb should be pointed in in the direction of the velocity,
index finger in the direction of the magnetic field and middle finger in the
direction of magnetic force.
When this is applied, we will discover that the index finger will point towards
the north region.
Read more on https://brainly.com/question/19904974
At a fixed point, P, the electric and magnetic field vectors in an electromagnetic wave oscillate at angular frequency w . At what angular frequency does the Poynting vector oscillate at that point
Answer:
Poynting vector oscillate at a frequency of 2omega
Explanation:
This is because The poynting vector is proportional to the cross product of electric and magnetic field vectors. So Because both fields oscillate sinusoidally with frequency w, trigonometric identities show that their product is a sinusoidal function of frequency of 2w.
g a conductor consists of an infinite number of adjacent wires, each infinitely long. If there are n wires per unit length, what is the magnitude of B~
Answer:
B=uonI/2
Explanation:
See attached file
At what angle should the axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light to (a) (1/3), (b) (1/10)
Answer:
35.3°
18.4°
Explanation:
a.
The first polariser polarises the unpolarised light reducing its intensity from I0 to I0/2. We have to reduce the intensity from I0/2 to I0/3.
Using to Law of Malus, I=I0cos²θ
cos²θ=I/I0=(I0/3)/I0/2 ,
cosθ=√2/3−−√=0.6667−−−−−√=0.8165
θ=cos−1(0.8165)=35.3∘
B.
Cos²θ=I/Io =Io/10/Io9
Cosθ= √9/10= 0.9487
= cos−10.9487
=18.4°
(a) The angle of polaroid such that intensity reduces by 1/3 is 35.26°
(b) The angle of polaroid such that intensity reduces by 1/10 is 63.43°
Angle of polarisation:According to the Malus Law: The intensity of light when passing through a polarizer is given by:
I = I₀cos²θ
where θ is the angle of the polarizer axis with the direction of polarization of the light
I₀ is the initial intensity
When an unpolarised light passes through a polarizer, θ varies from 0 to 2π, so the intensity after passing the first polarizer is :
I = I₀<cos²θ> { average of cos²θ, for 0<θ<2π}
I = I₀/2
Now, this emerging light passes through a second polarizer such that:
(a) the intensity is I' = I₀/3
From Malus Law:
I' = Icos²θ
I₀/3 = (I₀/2)cos²θ
cos²θ = 2/3
θ = 35.26°
(b) the intensity is I' = I₀/10
From Malus Law:
I' = Icos²θ
I₀/10 = (I₀/2)cos²θ
cos²θ = 1/5
θ = 63.43°
Learn more about Malus Law:
https://brainly.com/question/14177847?referrer=searchResults
Three fish of equal volume are swimming in a fish tank. They all have the same volume, but A has the greatest mass, B has less, and fish C has even less mass. (The differences are significant.)
The fish are swimming as shown. At that instant, how do the buoyant forces exerted by the water on the three fish rank?
A. BFB > BFA = BFC
B. BFB = BFA > BFC
C. BFB > BFA > BFC
D. BFA = BFB = BFC
E. Some other ranking
If the fish stopped swimming, fish B would remain right where it is shown.
What would happen to fish A and C? Put all the correct answers. If none of these would happen, put N.
A. Fish C would be pushed down to the bottom by the water above it.
B. Fish C would float to the top.
C. Fish A would be pushed to the top by the water below it.
D. Fish A would sink to the bottom.
Answer:
Fish C would float to the top & Fish A would sink to the bottom
Explanation:
A would sink to the bottom.Since B just remains where it is shown, its mass must balance the buoyant force and its weight must be equal to the weight of the water displaced. Since A is heavier, its weight will be greater than its buoyant force, it will sink. Since C is lighter, its buoyant force will be greater thanits weight and it will float to the top.
A charged particle is moving with speed v perpendicular to a uniform magnetic field. A second identical charged particle is moving with speed 2v perpendicular to the same magnetic field. If the frequency of revolution of the first particle is f, the frequency of revolution of the second particle is
Answer:
the frequency of revolution of the second particle is f
Explanation:
centripetal force is balanced by the magnetic force for object under magnetic field is given as
Mv²/r= qvB
But v= omega x r
Omega= 2pi x f
f= qB/2pi x M
So since frequency does not depend on the velocity.therefore the frequency of revolution of the second particle remains the same and its equal to f
In a system with only a single force acting upon a body, what is the relationship between the change in kinetic energy and the work done by the force?
Answer: W.D = 1/2mv^2
Explanation:
If an external force or a single force is acting on a body. Just like the first law of thermodynamics, the force acting on the body will cause work done on the system.
Work done = force × distance
And the work done on the body will cause the molecules of the body to experience motion and thereby producing kinetic energy.
The work done will be converted to kinetic energy.
W.D = 1/2mv^2
A certain shade of blue has a frequency of 7.06×1014 Hz. What is the energy E of exactly one photon of this light? Planck's constant h=6.626×10−34 J⋅s.
Answer:
Energy, [tex]E=4.67\times 10^{-19}\ J[/tex]
Explanation:
It is given that,
Frequency of blue shade is, [tex]f=7.06\times 10^{14}\ Hz[/tex]
We need to find the energy of exactly one photon of this light. The formula that is used to find the energy of photon is given by :
[tex]E=nhf[/tex]
Here, n is number of photon, n = 1
h is Planck's constant
So,
[tex]E=1\times 6.626\times 10^{-34}\times 7.06\times 10^{14}\\\\E=4.67\times 10^{-19}\ J[/tex]
So, the energy of this light is [tex]4.67\times 10^{-19}\ J[/tex].