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).
In 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