The danger signals are red while the eye is more sensitive to yellow because – (1) absorption in red is less than yellow and hence red is visible from a distance (2) scattering in yellow light is less than red (3) the wavelength of red light is more than yellow light (4) none of the above reasons

The danger signals are red while the eye is more sensitive to yellow because – (1) absorption in red is less than yellow and hence red is visible from a distance (2) scattering in yellow light is less than red (3) the wavelength of red light is more than yellow light (4) none of the above reasons
by

1 Answer

Answer :

(3) the wavelength of red light is more than yellow light
by
selected

Related questions

The danger signals are red while the eye is more sensitive to yellow because.

Description : The danger signals are red while the eye is more sensitive to yellow because.

Last Answer : The danger signals are red while the eye is more sensitive to yellow because.

Danger signals are generally red as red light – (1) is least bright (2) undergoes least deviation (3) has lowest velocity (4) gives comfort to eye

Description : Danger signals are generally red as red light – (1) is least bright (2) undergoes least deviation (3) has lowest velocity (4) gives comfort to eye

Last Answer : (2) undergoes least deviation Explanation: The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely ... red which has the highest wavelength of all the colours we can see is scattered the least.

Danger signals are generally red as red light (1) is least bright (2) undergoes least deviation (3) has lowest velocity (4) gives comfort to eye

Description : Danger signals are generally red as red light (1) is least bright (2) undergoes least deviation (3) has lowest velocity (4) gives comfort to eye 

Last Answer : undergoes least deviation 

The danger signals are red not yellow because

Description : The danger signals are red not yellow because

Last Answer : the wavelength of red light is more

Which of the following colors of visible light has the longest wavelength? Is it: w) violet x) green y) yellow z) red

Description : Which of the following colors of visible light has the longest wavelength? Is it: w) violet x) green y) yellow z) red

Last Answer : ANSWER: Z -- RED

In the Tyndall Effect, the intensity of scattered radiation is inversely proportional to the fourth power of the wavelength. Which one of the following colors of light would exhibit the most intense Tyndall scattering? w) yellow x) green y) orange z) violet

Description : In the Tyndall Effect, the intensity of scattered radiation is inversely proportional to the fourth power of the wavelength. Which one of the following colors of light would exhibit the most intense Tyndall scattering? w) yellow x) green y) orange z) violet 

Last Answer : ANSWER: Z -- VIOLET 

Scattering losses are caused by the interaction of light with density fluctuations within a fiber. What are the two scattering mechanisms called when the size of the density fluctuations is (a) greater than and (b) less than one-tenth of the operating wavelength?

Description : Scattering losses are caused by the interaction of light with density fluctuations within a fiber. What are the two scattering mechanisms called when the size of the density fluctuations is (a) greater than and (b) less than one-tenth of the operating wavelength?

Last Answer : . (a) Mie scattering; (b) Rayleigh scattering.

Red light is used for signals because it has – (1) long wavelength (2) high intensity (3) high frequency (4) low refraction in the medium

Description : Red light is used for signals because it has – (1) long wavelength (2) high intensity (3) high frequency (4) low refraction in the medium

Last Answer : (1) long wavelength Explanation: Red is the international colour of stop signs and stop lights on highways and intersections because it is scattered the least by air molecules. The effect of scattering is ... the colours and is able to travel the longest distance through fog, rain, and the alike.

Red light is used for signals because it has (1) long wavelength (2) high intensity (3) high frequency (4) low refraction in the medium

Description : Red light is used for signals because it has (1) long wavelength (2) high intensity (3) high frequency (4) low refraction in the medium

Last Answer : long wavelength

The sky appears blue because of – (1) Atmospheric water vapour (2) Scattering of light (3) Reflection on sea water (4) Emission of blue wavelength by the sun

Description : The sky appears blue because of – (1) Atmospheric water vapour (2) Scattering of light (3) Reflection on sea water (4) Emission of blue wavelength by the sun

Last Answer : (2) Scattering of light Explanation: The sky is blue because the molecules in the air scatter light in the higher wavelengths (that is, the blue light), while lower wavelength light (that is ... reflected down from the scattering is blue, therefore a blue sky. This is called Rayleigh scattering.

The sky appears blue because of (1) Atmospheric water vapour (2) Scattering of light (3) Reflection on sea water (4) Emision of blue wavelength by the sun

Description : The sky appears blue because of (1) Atmospheric water vapour (2) Scattering of light (3) Reflection on sea water (4) Emision of blue wavelength by the sun

Last Answer : Scattering of light

The sun appears red at sunrise and sunset while it appears white at noon because of _____ A. Refraction B. It is cooler at sunrise and at sunset C. Diffraction leading to red end of the spectrum reaching the earth D. Scattering of light due to dust particles and air molecules

Description : The sun appears red at sunrise and sunset while it appears white at noon because of _____ A. Refraction B. It is cooler at sunrise and at sunset C. Diffraction leading to red end of the spectrum reaching the earth D. Scattering of light due to dust particles and air molecules

Last Answer : ANSWER: D

The sun appears red at sunrise and sunset while it appears white at noon, because A. Of refraction B. It is cooler at sunrise and at sunset C. Of diffraction leading to red end of the spectrum reaching the earth. D. Of Scattering of light due to dust particles and air molecules?

Description : The sun appears red at sunrise and sunset while it appears white at noon, because A. Of refraction B. It is cooler at sunrise and at sunset C. Of diffraction leading to red end of the spectrum reaching the earth. D. Of Scattering of light due to dust particles and air molecules?

Last Answer : C. Of diffraction leading to red end of the spectrum reaching the earth.

Stars appear twinkling because of ______ of light. (1) Reflection (2) Scattering (3) Emission (4) Absorption

Description : Stars appear twinkling because of ______ of light. (1) Reflection (2) Scattering (3) Emission (4) Absorption

Last Answer : (2) Scattering Explanation: The stars' light must travel through the Earth's multi-layered atmosphere, and as it does so it is refracted (bent) multiple times and in random directions. The phenomenon of ... star wink as though it is in motion. It is this action that our eyes translate as twinkling.

Stars appear twinkling because of ......... of light. (1) Reflection (2) Scattering (3) Emission (4) Absorption

Description : Stars appear twinkling because of ......... of light. (1) Reflection (2) Scattering (3) Emission (4) Absorption

Last Answer : Scattering

An electron microscope gives higher magnification than an optical microscope, because: (1) It uses more powerful lenses (2) the velocity of electron is smaller than that of visible (3) the electrons have more energy than the light particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light

Description : An electron microscope gives higher magnification than an optical microscope, because: (1) It uses more powerful lenses (2) the velocity of electron is smaller than that of visible (3) the ... particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light

Last Answer : (4) the wavelength of electrons is smaller as compared to the wavelength of visible light Explanation: An electron microscope uses a beam of electrons to illuminate a specimen and produce a ... photons. Magnification is the process of enlarging something only in appearance, not in physical size.

An electron microscope gives higher magnifications than an optical microscope because – (1) The velocity of electrons is smaller than that of light (2) The wavelength of electrons is smaller as compared to the wavelength of visible light (3) The electrons have more energy than the light particulars (4) The electron microscope uses more powerful lenses

Description : An electron microscope gives higher magnifications than an optical microscope because - (1) The velocity of electrons is smaller than that of light (2) The wavelength of electrons is smaller as ... have more energy than the light particulars (4) The electron microscope uses more powerful lenses

Last Answer : (2) The wavelength of electrons is smaller as compared to the wavelength of visible light Explanation: An electron microscope is a microscope that uses a beam of accelerated electrons as a spume ... a higher resolving power than a light microscope and can reveal the structure of smaller objects.

An electron microscope gives higher magnifications than an optical microscope because : (1) The velocity of electrons is smaller than that of light (2) The wavelength of electrons is smaller as compared to the wavelength of visible light (3) The electrons have more energy than the light particulars (4) The electron microscope uses more powerful lenses

Description : An electron microscope gives higher magnifications than an optical microscope because : (1) The velocity of electrons is smaller than that of light (2) The wavelength of electrons is smaller as ... have more energy than the light particulars (4) The electron microscope uses more powerful lenses 

Last Answer : The wavelength of electrons is smaller as compared to the wavelength of visible light

An electron microscope gives higher magnification than an optical microscope, because : (1) it uses more powerful lenses (2) the velocity of electron is smaller than that of visible light (3) the electrons have more energy than the light particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light

Description : An electron microscope gives higher magnification than an optical microscope, because : (1) it uses more powerful lenses (2) the velocity of electron is smaller than that of visible light (3) ... particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light

Last Answer : the wavelength of electrons is smaller as compared to the wavelength of visible light

Wavelength longer than ______ m/μ is not visible to the eye, and are called infrared

Description : Wavelength longer than ______ m/μ is not visible to the eye, and are called infrared

Last Answer : Ans. 750

Wavelength longer than ______ m/μ is not visible to the eye, and are called infrared

Description : Wavelength longer than ______ m/μ is not visible to the eye, and are called infrared

Last Answer : Ans.750

The sun remains visible for some time after it actually sets below the horizon. This happens due to 1. atmospheric refraction 2. scattering of light 3. dispersion Which of the above statements is/are correct? (a) 1 only (b) 1 and 2 (c) 1 and 3 (d) 1, 2 and 3

Description : The sun remains visible for some time after it actually sets below the horizon. This happens due to 1. atmospheric refraction 2. scattering of light 3. dispersion Which of the above statements is/are correct? (a) 1 only (b) 1 and 2 (c) 1 and 3 (d) 1, 2 and 3

Last Answer : Ans:(a)

Which of the following HPLC detectors is used as a bulk property or general purpose detector? A. Electrochemical detector B. Fluorescence detector C. UV-Visible detector D. Evaporative Light scattering detector

Description : Which of the following HPLC detectors is used as a bulk property or general purpose detector? A. Electrochemical detector B. Fluorescence detector C. UV-Visible detector D. Evaporative Light scattering detector

Last Answer : D. Evaporative Light scattering detector

What is true for intensity of scattered light according to Rayleigh’s law? A. The intensity for scattering for light of largest wavelength more B. The light of smallest wavelength will be scattered more C. All the wavelengths are scattered equally D. Intensity of light is not affected by scattering

Description : What is true for intensity of scattered light according to Rayleigh's law? A. The intensity for scattering for light of largest wavelength more B. The light of smallest wavelength will be scattered ... C. All the wavelengths are scattered equally D. Intensity of light is not affected by scattering

Last Answer : B. The light of smallest wavelength will be scattered more

Assertion (A) :Sunlight reaches us without dispersion in the form of white light and not as a component. Reason(R) : Dispersion takes place due to variation of refractive index for different wavelength but in vaccum the speed of light is independent of wavelength and hence vaccum is a non- dispersive medium (a) Both A and R are true and R is the correct explanation of A. (b) Both A and R are true but R is not the correct explanation of A. (c) A is true but R is false. (d) A is false but R is true.

Description : Assertion (A) :Sunlight reaches us without dispersion in the form of white light and not as a component. Reason(R) : Dispersion takes place due to variation of refractive index for different wavelength but in vaccum the speed of ... of A. (c) A is true but R is false. (d) A is false but R is true.

Last Answer : (a) Both A and R are true and R is the correct explanation of A.

The colour of scattered light depends on (a) Size of scattering particles (b) Wavelength of light (c) Both (a) and (b) (d) None of the above

Description : The colour of scattered light depends on (a) Size of scattering particles (b) Wavelength of light (c) Both (a) and (b) (d) None of the above

Last Answer : (c) Both (a) and (b)

Red is used as an emergency or danger signal as – (1) it is a striking colour (2) its wavelength is the longest (3) it is scattered (4) it has very high energy

Description : Red is used as an emergency or danger signal as – (1) it is a striking colour (2) its wavelength is the longest (3) it is scattered (4) it has very high energy

Last Answer : (2) its wavelength is the longest Explanation: The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Red has the highest wavelength of all the colours and is able to travel the longest distance through fog, rain, and the alike.

Red is used as an emergency or danger signal as (1) it is a striking colour (2) its wavelength is the longest (3) it is scattered (4) it has very high energy

Description : Red is used as an emergency or danger signal as (1) it is a striking colour (2) its wavelength is the longest (3) it is scattered (4) it has very high energy

Last Answer : its wavelength is the longest

In PS I the reaction centre chlorophyll a has an absorption peak at 700 nm, hence is called (A)____ while in PS II it has absorption maxima at 680 nm

Description : In PS I the reaction centre chlorophyll a has an absorption peak at 700 nm, hence is called (A)____ while in PS II it has absorption maxima at 680 nm

Last Answer : In PS I the reaction centre chlorophyll a has an absorption peak at 700 nm, hence is called (A) ... absorption maxima at 680 nm and is called (B)____

The band of light frequencies that are too high to be seen by the human eye. ∙ A. Ultraviolet ∙ B. Visible light ∙ C. Infrared ∙ D. Yellow

Description : The band of light frequencies that are too high to be seen by the human eye. ∙ A. Ultraviolet ∙ B. Visible light ∙ C. Infrared ∙ D. Yellow

Last Answer : ∙ C. Infrared

A small hole in a sheet of aluminum foil is used to diffract yellow light both under water and in a vacuum. Which is true? w) light diffracts less in the water because its wavelength is larger. x) light diffracts less in the water because its wavelength is smaller. y) light diffracts more in the water because its wavelength is larger. z) light diffracts more in the water because its wavelength is smaller.

Description : A small hole in a sheet of aluminum foil is used to diffract yellow light both under water and in a vacuum. Which is true? w) light diffracts less in the water because its wavelength is ... because its wavelength is larger. z) light diffracts more in the water because its wavelength is smaller.

Last Answer : ANSWER: X -- LIGHT DIFFRACTS LESS IN THE WATER BECAUSE ITS WAVELENGTH IS SMALLER

Stars twinkle but planets do not twinkle because – (1) they emit light of a constant intensity (2) their distance from the earth does not change with time (3) they are very far away from the earth resulting in decrease in intensity of light (4) they are nearer to the earth and hence we receive a greater amount of light and therefore minor variations in intensity are not noticeable

Description : Stars twinkle but planets do not twinkle because - (1) they emit light of a constant intensity (2) their distance from the earth does not change with time (3) they are very far away ... and hence we receive a greater amount of light and therefore minor variations in intensity are not noticeable

Last Answer : (4) they are nearer to the earth and hence we receive a greater amount of light and therefore minor variations in intensity are not noticeable Explanation: Eris is the most massive and second-largest ... orbiting the Sun, and the largest known body in the Solar System not visited by a spacecraft.

Stars twinkle but planets do not twinkle because (1) they emit light of a constant intensity (2) their distance from the earth does not change with time (3) they are very far away from the earth resulting in decrease in intensity of light (4) they are nearer to the earth and hence we receive a greater amount of light and therefore minor variations in intensity are not noticeable

Description : Stars twinkle but planets do not twinkle because (1) they emit light of a constant intensity (2) their distance from the earth does not change with time (3) they are very far away from ... and hence we receive a greater amount of light and therefore minor variations in intensity are not noticeable 

Last Answer : they are nearer to the earth and hence we receive a greater amount of light and therefore minor variations in intensity are not noticeable

The blue colour of water in the sea is due to – (1) absorption of other colours except blue by water molecules (2) scattering of blue light by water molecules (3) reflection of blue light by impurities in sea water (4) reflection of blue sky by sea water

Description : The blue colour of water in the sea is due to – (1) absorption of other colours except blue by water molecules (2) scattering of blue light by water molecules (3) reflection of blue light by impurities in sea water (4) reflection of blue sky by sea water

Last Answer : (1) absorption of other colours except blue by water molecules Explanation: Almost all sunlight that enters the ocean is absorbed, except very close to the coast. The red, yellow, and green ... to the absorption and scattering of light. The blue wavelengths of light are scattered, similar to the

Fibre optics work on the principle of - (1) scattering of light (2) total internal absorption (3) total internal reflection (4) option rotation

Description : Fibre optics work on the principle of - (1) scattering of light (2) total internal absorption (3) total internal reflection (4) option rotation

Last Answer : (3) total internal reflection Explanation: An optical fibre is a cylindrical dielectric waveguide (non-conducting waveguide) that transmits light along its axis, by the process of total internal reflection.

Fibre optics work on the principle of – (1) Scattering of light (2) Total internal absorption (3) Total internal reflection (4) Optical rotation

Description : Fibre optics work on the principle of – (1) Scattering of light (2) Total internal absorption (3) Total internal reflection (4) Optical rotation

Last Answer : (3) Total internal reflection Explanation: An optical fiber (or optical fibre) is a flexible, transparent fiber made of glass (silica) or plastic, slightly thicker than a human hair. It ... science and engineering concerned with the design and application of optical fibers is known as fiber optics.

The loss in signal power as light travels down a fiber is called a. Dispersion b. Scattering c. Absorption d. Attenuation

Description : The loss in signal power as light travels down a fiber is called a. Dispersion b. Scattering c. Absorption d. Attenuation

Last Answer : d. Attenuation

Loss due to the diffraction of light when it strikes on the irregularities formed during the manufacturing process of the fiber optics. A. Absorption loss B. Attenuation C. Bending loss D. Rayleigh scattering loss

Description : Loss due to the diffraction of light when it strikes on the irregularities formed during the manufacturing process of the fiber optics. A. Absorption loss B. Attenuation C. Bending loss D. Rayleigh scattering loss

Last Answer : D. Rayleigh scattering loss

ECE Board Exam November 1996 The loss in signal power as light travels down a fiber is A. attenuation B. propagation C. absorption D. scattering

Description : ECE Board Exam November 1996 The loss in signal power as light travels down a fiber is A. attenuation B. propagation C. absorption D. scattering

Last Answer : A. attenuation

The blueness of the sky is mainly due to -------? A. The scattering of sunlight by air molecules (Answer) B. The presence of water vapor C. Absorption of blue light by the air D. Emission of blue light by the atmosphere

Description : The blueness of the sky is mainly due to -------? A. The scattering of sunlight by air molecules (Answer) B. The presence of water vapor C. Absorption of blue light by the air D. Emission of blue light by the atmosphere

Last Answer : A. The scattering of sunlight by air molecules (Answer)

Which of the following is not a factor in cable light loss? ∙ A. reflection ∙ B. absorption ∙ C. scattering ∙ D. dispersion

Description : Which of the following is not a factor in cable light loss? ∙ A. reflection ∙ B. absorption ∙ C. scattering ∙ D. dispersion

Last Answer : A. reflection

The loss in signal power as light travels down a fiber is called ∙ a. Dispersion ∙ b. Scattering ∙ c. Absorption ∙ d. Attenuation

Description : The loss in signal power as light travels down a fiber is called ∙ a. Dispersion ∙ b. Scattering ∙ c. Absorption ∙ d. Attenuation

Last Answer : ∙ d. Attenuation

The blue colour of water in the sea is due to (1) absorption of other colours except blue by water molecules (2) scattering of blue light by water molecules (3) reflection of blue light by impurities in sea water (4) reflection of blue sky by sea water

Description : The blue colour of water in the sea is due to (1) absorption of other colours except blue by water molecules (2) scattering of blue light by water molecules (3) reflection of blue light by impurities in sea water (4) reflection of blue sky by sea water

Last Answer : absorption of other colours except blue by water molecules

Fibre optics work on the principle of (1) scattering of light (2) total internal absorption (3) total internal reflection (4) optical rotation

Description : Fibre optics work on the principle of (1) scattering of light (2) total internal absorption (3) total internal reflection (4) optical rotation

Last Answer :  total internal reflection

Ordinary water is not used as a moderator because, it (A) Has a low absorption cross-section (B) Has a low scattering cross-section (C) Absorbs neutrons (D) Does not absorb neutrons

Description : Ordinary water is not used as a moderator because, it (A) Has a low absorption cross-section (B) Has a low scattering cross-section (C) Absorbs neutrons (D) Does not absorb neutrons

Last Answer : (C) Absorbs neutrons

Higher concentration of CO2 in atmosphere (A) Allows visible solar radiation (ultraviolet) of short wave-length to pass through (B) Reflects and absorbs the longer wavelength (infra-red) radiations (C) Prevents solar heat being radiated out completely, resulting in 'heat trap' i.e., global warming (D) All (A), (B) and (C)

Description : Higher concentration of CO2 in atmosphere (A) Allows visible solar radiation (ultraviolet) of short wave-length to pass through (B) Reflects and absorbs the longer wavelength (infra-red) radiations (C) Prevents solar heat being ... in 'heat trap' i.e., global warming (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

When considering visible light cured composites, which of the following statements is incorrect? A. An air-inhibited layer is present superficially on the composite. B. The wavelength of the light which affects the initiator is in the range of 450 to 500 nanometers. C. All other things equal. The light generally penetrates deeper into a small-particle composite than it does into a microfilled composite. (smaller particles absorb more light) D. B and C E. All are true

Description : When considering visible light cured composites, which of the following statements is incorrect? A. An air-inhibited layer is present superficially on the composite. B. The wavelength of the light which affects ... composite. (smaller particles absorb more light) D. B and C E. All are true

Last Answer : E. All are true

Which of the following colors is not found in the visible light wave spectrum? ∙ a. Red ∙ b. White ∙ c. Orange ∙ d. Yellow

Description : Which of the following colors is not found in the visible light wave spectrum? ∙ a. Red ∙ b. White ∙ c. Orange ∙ d. Yellow

Last Answer : b. White