answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
charle [14.2K]
2 years ago
12

A thin film of polystyrene is used as an antireflective coating for fabulite (known as the substrate). the index of refraction o

f the polystyrene is 1.49, and the index of refraction of the fabulite is 2.409. what is the minimum thickness of film required? assume that the wavelength of the light in air is 500 nanometers.
Physics
1 answer:
kvasek [131]2 years ago
6 0

To solve this problem, we assume that the wavelength of the light in air is 500 nanometers.

For this case we only need the refractive index of the polystyrene. For an antireflective coating, we need a quarter of wave thickness at the wavelength in the air. Which means that the antireflective coating needs to be as thick as 1/4 of the wavelength, divided by the coating’s refractive index. This is expressed mathematically in the form:

x = λ / (4 * n)

where,

x = thickness

λ = wavelength of light

n = index of refraction of polystyrene

Substituting:

x = 500 nm / (4 * 1.49)
x = 500 nm / 5.96
x = 83.90 nm

You might be interested in
Which of the following characteristics of Earth's relationship to the Sun explains the existence of Earth's seasons? Choose all
Aneli [31]

Answer:

Earth's axis is tilted relative to its orbital plane.

Earth orbits around the Sun, completing one orbit each year

Explanation:

The earth tilt at an angle causes the sun rays to hit the earth surface around the globe differently. Due to the oblique angle that the rays hit the subtropics and poles, there is less heat intensity compared to the equator where the sun rays hit the earth's surface at a more or less right angle.

The earth rotation around the sun also causes seasons coupled with the earth’s tilts. As the earth rotates, in one point in the orbit, the northern or southern hemispheres will be tilted towards the sun. The phenomenon varies the local temperatures of particular regions of the earth hence driving seasonal climatic changes.

6 0
2 years ago
A weather balloon is rising vertically from a launching pad on the ground. A technician standing 300 feet from the launching pad
avanturin [10]

Answer:

\dfrac{dh}{dt} =5\ ft/s

Explanation:

Let

h = height of balloon (in feet).

θ = angle made with line of sight and ground (in radians).

h = 300  tanθ

\dfrac{dh}{d\theta } = 300 sec^2\theta

now  \dfrac{dh}{dt} can be written as

\dfrac{dh}{dt} =\dfrac{dh}{d\theta }\times \dfrac{d\theta }{dt}

\dfrac{d\theta }{dt} = \dfrac{1}{120}\at \ \theta =\dfrac{\pi}{4}

When θ = π/4,

\dfrac{dh}{d\theta } = 300 sec^2\theta

\dfrac{dh}{d\theta } = 600

\dfrac{dh}{dt} =\dfrac{dh}{d\theta }\times \dfrac{d\theta }{dt}

\dfrac{dh}{dt} =600\times \dfrac{1}{120}

\dfrac{dh}{dt} =5\ ft/s

5 0
2 years ago
Uzupełnij zdania właściwymi sformułowaniami. Wyobraź sobie, że między linę a siodełko karuzeli łańcuchowej wmontowany jest siłom
iragen [17]

Explanation:

Here's a clearer rendering of the question requirements;

Complete the sentences with the correct wording. Imagine that a force gauge is mounted between the rope and the chain carousel saddle. If you do not touch your feet to the ground when the vehicle is stationary, the dynamometer indicates A / B. When the carousel turns, you will read C / D on the dynamometer.

A. Your weight with the saddle

C. Rope strength value

B. Your weight

D. Centripetal force value

3 0
2 years ago
A damped harmonic oscillator consists of a block of mass 2.5 kg attached to a spring with spring constant 10 N/m to which is app
Cerrena [4.2K]

Answer:

0.5% per oscillation

Explanation:

The term 'damped oscillation' means an oscillation that fades away with time. For Example; a swinging pendulum.

Kinetic energy, KE= 1/2×mv^2-------------------------------------------------------------------------------------------------------------(1).

Where m= Mass, v= velocity.

Also, Elastic potential energy,PE=1/2×kX^2----------------------------------------------------------------------------------------------------------------------(2).

Where k= force constant, X= displacement.

Mechanical energy= potential energy (when a damped oscillator reaches maximum displacement).

Therefore, we use equation (3) to get the resonance frequency,

W^2= k/m--------------------------------------------------------------------------------------(3)

Slotting values into equation (3).

= 10/2.5.

= ✓4.

= 2 s^-1.

Recall that, F= -kX

F^2= (-0.1)^2

Potential energy,PE= 1/2 ×0.01

Potential energy= 0.05 ×100

= 0.5% per oscillation.

6 0
2 years ago
You place a light bulb 8 cm in front of a concave mirror. You then move a sheet of paper back and forth in front of the mirror.
Alika [10]

sorry - late reply...just stumbled across tis...hope u can still use it :)


By the mirror equation: 1/di + 1/do = 1/f

<span>
</span>

<span>where di = distance to image = +12cm (+ for real image)</span>


and do = distance to object = +8cm


Substitute and solve for f, the focal length

<span><span>
1/12 + 1/8 = 1/f
</span><span>
1/f = (8 + 12) / 12 * 8 = 20/96
</span><span>
so f = 96/20 = 4.8 cm</span>
</span>
5 0
2 years ago
Other questions:
  • Which of the following are linear defects?. . An edge dislocation. . A Frenkel defect. . A screw dislocation. . A Schottky defec
    6·1 answer
  • a truss is made by hinging two uniform, 150-N rafters as shown in Fig. 5-21. They rest on an essentially frictionless floor and
    6·1 answer
  • A gannet is a seabird that fishes by diving from a great height
    12·1 answer
  • An electron moving at right angles to a 0.1 T magnetic field experiences an acceleration of 6 × 1015 m.s-2. What is the speed of
    12·1 answer
  • (8%) Problem 9: Helium is a very important element for both industrial and research applications. In its gas form it can be used
    8·1 answer
  • Describe the distribution of wdiff in terms of its center, shape, and spread, including any plots you use
    6·1 answer
  • Water is boiled at 300 kPa pressure in a pressure cooker. The cooker initially contains 3 kg of water. Once boiling started, it
    10·1 answer
  • A gold wire that is 1.8 mm in diameter and 15 cm long carries a current of 260 mA. How many electrons per second pass a given cr
    14·1 answer
  • A diffusion couple composed of two silver– gold alloys is formed; these alloys have compositions of 98 wt% Ag–2 wt% Au and 95 wt
    10·1 answer
  • Lucy is cruising through space in her new spaceship. As she coasts along, a tiny spacebug drifts into her path and bounces off t
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!