When light waves pass from air to glass, two main phenomena are affected: wavelength and velocity. The correct answer is [D] Only wavelength and velocity. The frequency of the light wave, which determines its color, remains constant because it is determined by the source emitting the light. However,Read more
When light waves pass from air to glass, two main phenomena are affected: wavelength and velocity. The correct answer is [D] Only wavelength and velocity. The frequency of the light wave, which determines its color, remains constant because it is determined by the source emitting the light. However, as light enters a medium like glass with a higher refractive index than air, the wavelength of the light wave decreases. This change occurs because the speed of light in glass is slower than in air, causing the wavelength to shorten. Additionally, the velocity of light decreases in glass due to its denser molecular structure compared to air. Option A is incorrect because the shape of the wave front remains unchanged, and only the wavelength and velocity are affected. Option B is incorrect because the frequency remains constant. Option C is incorrect because only the wavelength and velocity change, not the frequency. Therefore, when light passes from air to glass, the phenomena affected are primarily wavelength and velocity (option D).
Among the options provided, blue light has the highest energy. The correct answer is [A] Blue light. Light energy is determined by its wavelength and frequency, with shorter wavelengths corresponding to higher frequencies and higher energy photons. Blue light has a relatively shorter wavelength (aroRead more
Among the options provided, blue light has the highest energy. The correct answer is [A] Blue light. Light energy is determined by its wavelength and frequency, with shorter wavelengths corresponding to higher frequencies and higher energy photons. Blue light has a relatively shorter wavelength (around 450-495 nanometers) compared to green, red, and yellow light. The energy of a photon is directly proportional to its frequency (E = hf, where E is energy, h is Planck’s constant, and f is frequency), meaning higher frequency light like blue light carries more energy per photon. Option B, green light, has a longer wavelength and lower energy compared to blue light. Option C, red light, has an even longer wavelength and lower energy than green light. Option D, yellow light, falls between green and red in wavelength and energy. Therefore, blue light (option A) has the highest energy among the choices provided due to its shorter wavelength and higher frequency compared to the other wavelengths of light listed.
Plants absorb intensely blue and red light wavelengths. The correct answer is [B] Blue and red. Chlorophyll, the primary pigment in plants responsible for photosynthesis, absorbs light most efficiently in the blue (around 450 nm) and red (around 660 nm) regions of the spectrum. These wavelengths corRead more
Plants absorb intensely blue and red light wavelengths. The correct answer is [B] Blue and red. Chlorophyll, the primary pigment in plants responsible for photosynthesis, absorbs light most efficiently in the blue (around 450 nm) and red (around 660 nm) regions of the spectrum. These wavelengths correspond to peaks in the absorption spectrum of chlorophyll, allowing plants to capture and convert light energy into chemical energy through photosynthesis. Option A, violet and orange, and option D, yellow and violet, do not align with the optimal absorption spectra of chlorophyll for photosynthesis. Option C, indigo and yellow, also do not match the wavelengths most effectively absorbed by chlorophyll. Therefore, the wavelengths of blue and red light (option B) are crucial for driving photosynthesis in plants, providing the energy needed for their growth, development, and metabolic processes.
Jena glass is capable of scattering ultraviolet (UV) rays due to additives like cerium oxide incorporated into its composition. The correct answer is [C] Jena glass. These additives absorb and scatter UV radiation effectively, making Jena glass suitable for applications requiring UV protection. ThisRead more
Jena glass is capable of scattering ultraviolet (UV) rays due to additives like cerium oxide incorporated into its composition. The correct answer is [C] Jena glass. These additives absorb and scatter UV radiation effectively, making Jena glass suitable for applications requiring UV protection. This includes optical lenses, scientific instruments, and protective eyewear where shielding against harmful UV rays is essential. Option A, soda glass, does not possess inherent UV scattering properties and is used in everyday glassware. Option B, Pyrex glass, is known for its resistance to thermal shock and is not specifically designed for UV protection. Option D, Crookes glass, is used in scientific instruments and cathode ray tubes but does not inherently scatter UV rays. Therefore, Jena glass (option C) stands out as the type of glass capable of effectively scattering ultraviolet rays due to its composition and additives designed for UV protection and absorption.
Stars twinkle due to atmospheric refraction. The correct answer is [A] Due to refraction. As starlight travels through Earth's atmosphere, it passes through layers of varying temperature and density. These atmospheric layers cause the light to refract, or bend, slightly in different directions. TheRead more
Stars twinkle due to atmospheric refraction. The correct answer is [A] Due to refraction. As starlight travels through Earth’s atmosphere, it passes through layers of varying temperature and density. These atmospheric layers cause the light to refract, or bend, slightly in different directions. The slight bending of light rays results in the apparent twinkling or shimmering of stars when observed from the ground. This effect is more pronounced when stars are near the horizon, where their light passes through a thicker layer of atmosphere. Option B, reflection, does not cause stars to twinkle as stars do not reflect light like surfaces do. Option C, polarization, refers to the orientation of light waves and does not directly cause twinkling. Option D, scattering, refers to the redirection of light rays in different directions due to particles in the atmosphere but is not the primary cause of star twinkling. Therefore, the twinkling of stars is primarily due to atmospheric refraction (option A), which causes the starlight to bend and fluctuate as it passes through varying atmospheric conditions.
Fiber optic communication transmits signals in the form of light waves. The correct answer is [A] Light wave. Optical fibers, made of glass or plastic, carry data using pulses of light that travel along their cores. These light waves represent digital information encoded as on-off pulses, allowing fRead more
Fiber optic communication transmits signals in the form of light waves. The correct answer is [A] Light wave. Optical fibers, made of glass or plastic, carry data using pulses of light that travel along their cores. These light waves represent digital information encoded as on-off pulses, allowing for high-speed and efficient transmission over long distances. Option B, radio waves, and option C, microwave waves, are used in wireless communication systems, not in fiber optics. Option D, electric waves, typically refers to electrical signals conducted through wires, which are not used for long-distance data transmission in fiber optics. Fiber optic communication’s reliance on light waves ensures minimal signal loss and interference, making it suitable for high-performance telecommunications and internet connectivity. Therefore, the signal flow in fiber optic communication is primarily in the form of light waves (option A).
Before setting, the Sun appears elliptical due to atmospheric refraction. The correct answer is [C] There is an effect of refraction of light. As the Sun nears the horizon, its light travels through a thicker layer of Earth's atmosphere. This atmospheric layer bends the Sun's light rays slightly, caRead more
Before setting, the Sun appears elliptical due to atmospheric refraction. The correct answer is [C] There is an effect of refraction of light. As the Sun nears the horizon, its light travels through a thicker layer of Earth’s atmosphere. This atmospheric layer bends the Sun’s light rays slightly, causing them to follow a curved path. The refraction effect is stronger near the horizon because the light passes through more of the atmosphere’s denser layers. This bending of light results in the Sun appearing distorted and stretched out horizontally, giving it an elliptical or flattened shape. Option A is incorrect because the Sun does not change its actual shape. Option B, light scattering, does not cause the Sun to appear elliptical but may affect its color or brightness. Option D, diffraction of light, involves bending of light around obstacles and is not responsible for the elliptical appearance of the Sun at sunset. Therefore, the correct explanation is the refraction of light (option C), which occurs due to the bending of light rays as they pass through the Earth’s atmosphere near the horizon.
A concave lens, also called a diverging lens, is used to correct nearsightedness (myopia). The correct answer is [C] Nearsightedness. Nearsightedness is a common vision condition where distant objects appear blurry while close objects are seen clearly. This occurs because the eyeball is too long orRead more
A concave lens, also called a diverging lens, is used to correct nearsightedness (myopia). The correct answer is [C] Nearsightedness. Nearsightedness is a common vision condition where distant objects appear blurry while close objects are seen clearly. This occurs because the eyeball is too long or the cornea is too curved, causing light rays to focus in front of the retina rather than directly on it. A concave lens diverges (spreads out) the incoming light rays before they reach the eye’s lens, allowing the focal point to be shifted back onto the retina. This correction enables individuals with myopia to see distant objects more clearly. Options A and D are incorrect because cataract is corrected through surgery, not with a concave lens, and long-sightedness (hypermetropia) is corrected with a convex lens. Option B, farsightedness (hyperopia), is corrected using a convex lens to converge light rays onto the retina for clear vision of near objects. Therefore, a concave lens specifically corrects nearsightedness (option C).
Galileo Galilei, an Italian astronomer and physicist, is credited with inventing the telescope around 1609. The correct answer is [A] Galileo. Galileo's telescope was a significant improvement over existing designs, allowing him to observe celestial objects with greater detail and clarity. His obserRead more
Galileo Galilei, an Italian astronomer and physicist, is credited with inventing the telescope around 1609. The correct answer is [A] Galileo. Galileo’s telescope was a significant improvement over existing designs, allowing him to observe celestial objects with greater detail and clarity. His observations, including the phases of Venus and the moons of Jupiter, provided compelling evidence for the heliocentric model of the solar system proposed by Copernicus. This revolutionary instrument fundamentally changed our understanding of the universe and paved the way for modern astronomy. Johannes Gutenberg (option B) invented the printing press, Thomas Edison (option C) invented the phonograph and electric light bulb, and Alexander Graham Bell (option D) invented the telephone, none of which are related to the invention of the telescope. Thus, Galileo Galilei remains widely recognized as the inventor of the telescope and a key figure in the history of science.
A telescope is an optical instrument designed specifically to observe distant objects in space. It works by collecting and focusing light from celestial bodies such as stars, planets, and galaxies. Telescopes can be either refracting (using lenses) or reflecting (using mirrors) in design, and they cRead more
A telescope is an optical instrument designed specifically to observe distant objects in space. It works by collecting and focusing light from celestial bodies such as stars, planets, and galaxies. Telescopes can be either refracting (using lenses) or reflecting (using mirrors) in design, and they come in various sizes and configurations to suit different observational needs. Telescopes are crucial tools in astronomy, allowing astronomers to explore the universe and study celestial phenomena. Option A, a simple microscope, is used for viewing small objects at low magnification and is not suitable for observing distant celestial objects. Option B, a compound microscope, is used for magnifying microscopic specimens in biological and medical research. Option C, an electron microscope, is used to observe very small objects at high magnification using a beam of electrons rather than light. Therefore, the correct optical instrument for observing distant objects, such as those in space, is the telescope (option D).
When waves of light pass from air to glass, then which phenomena will be affected?
When light waves pass from air to glass, two main phenomena are affected: wavelength and velocity. The correct answer is [D] Only wavelength and velocity. The frequency of the light wave, which determines its color, remains constant because it is determined by the source emitting the light. However,Read more
When light waves pass from air to glass, two main phenomena are affected: wavelength and velocity. The correct answer is [D] Only wavelength and velocity. The frequency of the light wave, which determines its color, remains constant because it is determined by the source emitting the light. However, as light enters a medium like glass with a higher refractive index than air, the wavelength of the light wave decreases. This change occurs because the speed of light in glass is slower than in air, causing the wavelength to shorten. Additionally, the velocity of light decreases in glass due to its denser molecular structure compared to air. Option A is incorrect because the shape of the wave front remains unchanged, and only the wavelength and velocity are affected. Option B is incorrect because the frequency remains constant. Option C is incorrect because only the wavelength and velocity change, not the frequency. Therefore, when light passes from air to glass, the phenomena affected are primarily wavelength and velocity (option D).
See lessWhich of the following has the highest energy?
Among the options provided, blue light has the highest energy. The correct answer is [A] Blue light. Light energy is determined by its wavelength and frequency, with shorter wavelengths corresponding to higher frequencies and higher energy photons. Blue light has a relatively shorter wavelength (aroRead more
Among the options provided, blue light has the highest energy. The correct answer is [A] Blue light. Light energy is determined by its wavelength and frequency, with shorter wavelengths corresponding to higher frequencies and higher energy photons. Blue light has a relatively shorter wavelength (around 450-495 nanometers) compared to green, red, and yellow light. The energy of a photon is directly proportional to its frequency (E = hf, where E is energy, h is Planck’s constant, and f is frequency), meaning higher frequency light like blue light carries more energy per photon. Option B, green light, has a longer wavelength and lower energy compared to blue light. Option C, red light, has an even longer wavelength and lower energy than green light. Option D, yellow light, falls between green and red in wavelength and energy. Therefore, blue light (option A) has the highest energy among the choices provided due to its shorter wavelength and higher frequency compared to the other wavelengths of light listed.
See lessWhich of the following types of light is absorbed intensely by plants?
Plants absorb intensely blue and red light wavelengths. The correct answer is [B] Blue and red. Chlorophyll, the primary pigment in plants responsible for photosynthesis, absorbs light most efficiently in the blue (around 450 nm) and red (around 660 nm) regions of the spectrum. These wavelengths corRead more
Plants absorb intensely blue and red light wavelengths. The correct answer is [B] Blue and red. Chlorophyll, the primary pigment in plants responsible for photosynthesis, absorbs light most efficiently in the blue (around 450 nm) and red (around 660 nm) regions of the spectrum. These wavelengths correspond to peaks in the absorption spectrum of chlorophyll, allowing plants to capture and convert light energy into chemical energy through photosynthesis. Option A, violet and orange, and option D, yellow and violet, do not align with the optimal absorption spectra of chlorophyll for photosynthesis. Option C, indigo and yellow, also do not match the wavelengths most effectively absorbed by chlorophyll. Therefore, the wavelengths of blue and red light (option B) are crucial for driving photosynthesis in plants, providing the energy needed for their growth, development, and metabolic processes.
See lessWhich one of the following types of glasses can scatter ultraviolet rays?
Jena glass is capable of scattering ultraviolet (UV) rays due to additives like cerium oxide incorporated into its composition. The correct answer is [C] Jena glass. These additives absorb and scatter UV radiation effectively, making Jena glass suitable for applications requiring UV protection. ThisRead more
Jena glass is capable of scattering ultraviolet (UV) rays due to additives like cerium oxide incorporated into its composition. The correct answer is [C] Jena glass. These additives absorb and scatter UV radiation effectively, making Jena glass suitable for applications requiring UV protection. This includes optical lenses, scientific instruments, and protective eyewear where shielding against harmful UV rays is essential. Option A, soda glass, does not possess inherent UV scattering properties and is used in everyday glassware. Option B, Pyrex glass, is known for its resistance to thermal shock and is not specifically designed for UV protection. Option D, Crookes glass, is used in scientific instruments and cathode ray tubes but does not inherently scatter UV rays. Therefore, Jena glass (option C) stands out as the type of glass capable of effectively scattering ultraviolet rays due to its composition and additives designed for UV protection and absorption.
See lessStars twinkle
Stars twinkle due to atmospheric refraction. The correct answer is [A] Due to refraction. As starlight travels through Earth's atmosphere, it passes through layers of varying temperature and density. These atmospheric layers cause the light to refract, or bend, slightly in different directions. TheRead more
Stars twinkle due to atmospheric refraction. The correct answer is [A] Due to refraction. As starlight travels through Earth’s atmosphere, it passes through layers of varying temperature and density. These atmospheric layers cause the light to refract, or bend, slightly in different directions. The slight bending of light rays results in the apparent twinkling or shimmering of stars when observed from the ground. This effect is more pronounced when stars are near the horizon, where their light passes through a thicker layer of atmosphere. Option B, reflection, does not cause stars to twinkle as stars do not reflect light like surfaces do. Option C, polarization, refers to the orientation of light waves and does not directly cause twinkling. Option D, scattering, refers to the redirection of light rays in different directions due to particles in the atmosphere but is not the primary cause of star twinkling. Therefore, the twinkling of stars is primarily due to atmospheric refraction (option A), which causes the starlight to bend and fluctuate as it passes through varying atmospheric conditions.
See lessIn what form does the signal flow in fiber optical communication?
Fiber optic communication transmits signals in the form of light waves. The correct answer is [A] Light wave. Optical fibers, made of glass or plastic, carry data using pulses of light that travel along their cores. These light waves represent digital information encoded as on-off pulses, allowing fRead more
Fiber optic communication transmits signals in the form of light waves. The correct answer is [A] Light wave. Optical fibers, made of glass or plastic, carry data using pulses of light that travel along their cores. These light waves represent digital information encoded as on-off pulses, allowing for high-speed and efficient transmission over long distances. Option B, radio waves, and option C, microwave waves, are used in wireless communication systems, not in fiber optics. Option D, electric waves, typically refers to electrical signals conducted through wires, which are not used for long-distance data transmission in fiber optics. Fiber optic communication’s reliance on light waves ensures minimal signal loss and interference, making it suitable for high-performance telecommunications and internet connectivity. Therefore, the signal flow in fiber optic communication is primarily in the form of light waves (option A).
See lessBefore setting, the Sun appears elliptical because
Before setting, the Sun appears elliptical due to atmospheric refraction. The correct answer is [C] There is an effect of refraction of light. As the Sun nears the horizon, its light travels through a thicker layer of Earth's atmosphere. This atmospheric layer bends the Sun's light rays slightly, caRead more
Before setting, the Sun appears elliptical due to atmospheric refraction. The correct answer is [C] There is an effect of refraction of light. As the Sun nears the horizon, its light travels through a thicker layer of Earth’s atmosphere. This atmospheric layer bends the Sun’s light rays slightly, causing them to follow a curved path. The refraction effect is stronger near the horizon because the light passes through more of the atmosphere’s denser layers. This bending of light results in the Sun appearing distorted and stretched out horizontally, giving it an elliptical or flattened shape. Option A is incorrect because the Sun does not change its actual shape. Option B, light scattering, does not cause the Sun to appear elliptical but may affect its color or brightness. Option D, diffraction of light, involves bending of light around obstacles and is not responsible for the elliptical appearance of the Sun at sunset. Therefore, the correct explanation is the refraction of light (option C), which occurs due to the bending of light rays as they pass through the Earth’s atmosphere near the horizon.
See lessConcave lens is used to correct
A concave lens, also called a diverging lens, is used to correct nearsightedness (myopia). The correct answer is [C] Nearsightedness. Nearsightedness is a common vision condition where distant objects appear blurry while close objects are seen clearly. This occurs because the eyeball is too long orRead more
A concave lens, also called a diverging lens, is used to correct nearsightedness (myopia). The correct answer is [C] Nearsightedness. Nearsightedness is a common vision condition where distant objects appear blurry while close objects are seen clearly. This occurs because the eyeball is too long or the cornea is too curved, causing light rays to focus in front of the retina rather than directly on it. A concave lens diverges (spreads out) the incoming light rays before they reach the eye’s lens, allowing the focal point to be shifted back onto the retina. This correction enables individuals with myopia to see distant objects more clearly. Options A and D are incorrect because cataract is corrected through surgery, not with a concave lens, and long-sightedness (hypermetropia) is corrected with a convex lens. Option B, farsightedness (hyperopia), is corrected using a convex lens to converge light rays onto the retina for clear vision of near objects. Therefore, a concave lens specifically corrects nearsightedness (option C).
See lessThe telescope was invented by
Galileo Galilei, an Italian astronomer and physicist, is credited with inventing the telescope around 1609. The correct answer is [A] Galileo. Galileo's telescope was a significant improvement over existing designs, allowing him to observe celestial objects with greater detail and clarity. His obserRead more
Galileo Galilei, an Italian astronomer and physicist, is credited with inventing the telescope around 1609. The correct answer is [A] Galileo. Galileo’s telescope was a significant improvement over existing designs, allowing him to observe celestial objects with greater detail and clarity. His observations, including the phases of Venus and the moons of Jupiter, provided compelling evidence for the heliocentric model of the solar system proposed by Copernicus. This revolutionary instrument fundamentally changed our understanding of the universe and paved the way for modern astronomy. Johannes Gutenberg (option B) invented the printing press, Thomas Edison (option C) invented the phonograph and electric light bulb, and Alexander Graham Bell (option D) invented the telephone, none of which are related to the invention of the telescope. Thus, Galileo Galilei remains widely recognized as the inventor of the telescope and a key figure in the history of science.
See lessWhich optical instrument is used to observe distant objects?
A telescope is an optical instrument designed specifically to observe distant objects in space. It works by collecting and focusing light from celestial bodies such as stars, planets, and galaxies. Telescopes can be either refracting (using lenses) or reflecting (using mirrors) in design, and they cRead more
A telescope is an optical instrument designed specifically to observe distant objects in space. It works by collecting and focusing light from celestial bodies such as stars, planets, and galaxies. Telescopes can be either refracting (using lenses) or reflecting (using mirrors) in design, and they come in various sizes and configurations to suit different observational needs. Telescopes are crucial tools in astronomy, allowing astronomers to explore the universe and study celestial phenomena. Option A, a simple microscope, is used for viewing small objects at low magnification and is not suitable for observing distant celestial objects. Option B, a compound microscope, is used for magnifying microscopic specimens in biological and medical research. Option C, an electron microscope, is used to observe very small objects at high magnification using a beam of electrons rather than light. Therefore, the correct optical instrument for observing distant objects, such as those in space, is the telescope (option D).
See less