Copy of David Werner - HW 16-2A Color on 2020-10-0

( Why? From fireworks to stars, the color of light is useful in finding out what's in matter. The emission of g by hydrogen and other atoms has played a key role in understanding the electronic structure of atoms. Trace materials, such as evidence from a crime scene, lead in paint or mercury in drinking water, can be identified by heating or burning the materials and examining the color(s) of light given off in the form of bright-line spectra. Model 1 - White Light Lightbulb (white light) Prism Color Reds Oranges Yellows Greens Blues Violets Photon Energy (x 10-2¹) (J) 269-318 318-337 337-352 352-382 382-452 452-523 2. What happens to white light when it passes through a prism? Wavelength Range (nm) 625-740 590-625 565-590 520-565 440-520 380-440 Speed (m/s) 3.00 x 108 3.00 x 108 3.00 × 108 3.00 x 108 3.00 x 108 3.00 x 108

State following statements whether TRUE or FALSE. i. We can see ordinary solid objects because light is refracted from them. ii. At room temperature the thermal radiation are in infrared region of the spectrum. iii. Our eyes are sensitive to ultraviolet light. iv. Upon heating, objects begin to emit visible light. Temperature of a piece of metal is increases; first it glow with deep red color and then it turns to yellow. V.

2.What is the speed of light in water (1=1.33) and in glass (1=1.5)? 3.What is the longest wavelength EM radiation that can eject a photoelectron from silver (A=4.73 eV; 1 eV = 1.6x10-19 J).

10. Of the available choices, the color most energetic. has the shortest wavelength and is the a. Blue b. White c. Red d. Black e. Green 11. Which of the following is not true regarding electrmagnetic energy? a. Electromagnetic energy travels through empty space b. All wavelengths of electromagnetic energy travel at the same speed c. The visible portion of the spectrum ccomprises only a small part of the total range of electromagnetic energy. d. A given wavelength is directly proportional to the energy contained in that wavelength e. The hotter an object, the more energy it emits at all wavelengths 12. Which wavelength contains the most energy? а. 25 um b. .05um c. 1.5μm d. 100um е. .001um 13. The amount of energy as the wavelength a. increases; increases b. decreases; increases c. decreases; decreases 14. The sensation of heat is produced by a. visible light b. x-rays c. radiowaves d. infrared e. ultra-violet in the northern hemisphere and rotate 15. Cyclones rotate in the southern…

1. Suppose you pass light from a Laser through two slits separated by 4.16 um and found that the second bright line on a screen is formed at an angle of 13 deg relative to the incident beam. a. What is the wavelength of the light? b. What is the enegy gap in eV c. What is the highest-order constructive interference possible with the system?

4. What is the equation of motion of a point-like particle with charge q and mass m in an electromagnetic field (Ē, B). Neglect the emission of radiation by the moving charge. Determi- ne the temporal change of the energy W of the particle in the external field. 5. A circularly polarized monochromatic wave is described by Ē(r,t) = E(cos(kz – wt), sin(kz – wt), 0) - (1) Compute the corresponding magnetic induction B(r,t). Assume the underlying medium is va- cuum. 6. Consider the particle from 4 moving in the field of 5. Formulate the equation of motion! 7. Let the particle at t = 0 be at the origin of coordinates. How should the initial conditi- ons for the velocity be chosen in order to keep the energy W of the particle constant? Please do Part 7 7 only

What can be considered as coherent light?A. violet light and blue lightB. red light (λ = 740 nm) and red light ( λ = 700 nm)C. green light (λ = 530 nm) and green light ( λ = 540 nm)D. yellow light (λ = 570 nm) and yellow light ( λ = 570 nm)

2. A solar panel is mounted on the roof of a house. The panel is positioned at the following coordinates (measured in meters): A(8,0,0), B(8,18,0), C(0,0,8) and D(0,0,8). Let the vector S represent the intensity, in watts per square meters, having the direction of the sun's rays. B. Given that information: a) Find normal vector N where N = AB x AD (hint: find vectors AB and AD first!) b) Use N to find the area of the panel. 900 900 900, V3' v3 ' V3 c) Assuming S = (in watts per sq. meters), what is the intensity of the sun? d) What is the amount of electrical power the panel can produce? e) What is the angle, in degrees, between S and N? Round to the hundredths.

1. Do all hot objects radiate light? If hot water is placed in a vacuum in total darkness will it radiate heat? Recall that heat is detected through night-vision goggles. These devices "see" infra-red light emitted by hot objects. This is evidence that heat is a part of the spectrum and therefore it can travel through a vacuum just as the other components of light. If so, then heat should travel as fast as light through a vacuum. It should travel just as fast through air. Why then does the air gap inside the thermos bottle retard the loss of heat from the hot water inside? 2. The coefficient of linear expansion of aluminum is 0.000023/C. An aluminum rod 5 meters long is heated so that its temperature rises from 25 °C to 50 °C. What is the change in its length? 3. A rectangular block of concrete has a volume of 5 cubic meters and initial temperature of 30°C. By how much will it expand if the temperature rises by 5 C°? The coefficient of thermal expansion of concrete is 10/C. 4.…

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As the ray travels from air ( n = 1.00) to water (n = 1.33), the critical angel for this transition is ?   a.) does not exist. b.)is equal to 41.2∘   c.) is equal to 138.8∘ d.)is equal to 48.8∘

1. You have orange light with a wavelength of 615 nm. a. What is the frequency of this light? b. What is the energy of one photon of this light?

answer numbers 18,19,10 true or false

1. If the visible wavelength lies between 300 nm - 800 nm, what is the interval expressed in eV? 2. Which transition in the hydrogen atom produces visible light?

2. If light passes through a piece of tinted glass, 35% is absorbed. Then, it passes through second piece of tinted glass, another 35% is absorbed. So what is the final percentage that passes through both, compared to original 100%? a. 30%, b. 65%, c. 42.3%, d. 22.8%

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3. What is the longest wavelength EM radiation that can eject a photoelectron from silver (A-4.73 eV; 1 eV = 1.6x1019 J). 4. If someone wanted to build a scale model of the atom with a

What is the defining characteristic of a perfect blackbody? a. It looks black in ordinary white light.   b. It absorbs all radiation incident on it.   c. The temperature of a glacier increased over time.   d. It has a surface temperature of absolute zero.   e. It has a surface that reflects 50% of light evenly across all frequencies

Dispersion occurs when:a. some materials bend light more than other materials.b. a material slows down some wavelengths more than others.c. a material changes some frequencies more than others.d. light has different speeds in different materials.

1. If all parts of a light beam have a constant phase relationship, with the same wavelength and frequency, the light beam is polychromatic and coherent. А. True в. False 2. It is the wave theory of light that offers the only explanation for the ability of light to exhibit interference. O A. False В. True 3. The photon model of light is more appropriate that the wave model in explaining photoelectric emission. O A. False В. Тrue 4. If the screen is moved closer to the slits, the distance between the central maximum and the first maximum will remain the same.

Its solid state physics

1. What color is the complementary color of yellow? *A. cyanB. magentaC. blueD. red

3. Which of the following statement is correct? A. Violet is less energetic than blue B. Yellow is brighter than orange. C. Orange is energetic than red D. Visible light may different frequencies but of the same energy

The Sun appears to be red as it sets because:1. Air absorbs red light less than other frequencies (i.e., acts like a red filter).2. The sunlight has a red shift when you're moving fastest away from it.3. The Sun cools down to 5000 K each evening.4. Light is refracted as it enters the atmosphere.5. The Sun dies in a glorious fireball each evening and is reborn each morning.6. None of the above.

1 . Longer wavelengths of ultraviolet light (UV-A), which range from 400 nm to 315 nm, are absorbed principally in the lens of the cornea. True or False 2. Modelocked lasers – “lock” together multiple longitudinal modes so that a laser simultaneously oscillates on all of them to emit very short pulses. True or False

Normal human body temperature is about 37°C. What is this temperature in kelvins? What is the peak wavelength emitted by a person with this temperature? What color is this? Explain

5. A. Please rearrange the light bulks from high temperature to low temperature. a. B. Why is this the right order? C. If you have a green light bulk, its temperature is between which two lights?