Related Questions

Read the following passage carefully and choose the most appropriate answer to the question out of the four alternatives.
The human eye is a complex part of the body that is used for seeing. Eyes enable people to perform daily tasks and to learn about the world that surrounds them. Sight, or vision, is a rapidly occurring process that involves continuous interaction between the eye, the nervous system, and the brain. When someone looks at an object, what he really sees is the light reflected from the object. This reflected light passes through the lens and falls on the retina of the eye. Here the light induces nerve impulses that travel through the optic nerve to the brain and then over other nerves to muscles and glands.
The eye is similar to a television camera. Both the eye and the television camera convert light energy to electrical energy. The eye converts light to nerve impulses that are interpreted by the brain as the sense perception called sight. A television camera converts light to electronic signals that are broadcast and transformed into light images in a television receiver. It is wonderful that human eyes blink an average of once every six seconds. This washes the eye with the salty secretion from the tear or lachrymal glands. Each tear gland is about the size and shape of an almond. These glands are situated behind the upper eyelid at the outer corner of the eye. After passing over the eye, the liquid from the gland is drained into the nose through the tear duct at the inner corner of the eye. The sense perception that the brain releases after the eye converts light to nerve impulses is known as
Consider the following statements about visible light, UV light and X-ray.
1. The wavelength of visible light is more than that of X-ray.
2. The energy of X-ray photons is higher than that of UV light photons.
3. The energy of UV light photons is less than that of visible light photons.
Which of the statement(s) given above is/are correct?
Read the following passage carefully and choose the most appropriate answer to the question out of the four alternatives.
The human eye is a complex part of the body that is used for seeing. Eyes enable people to perform daily tasks and to learn about the world that surrounds them. Sight, or vision, is a rapidly occurring process that involves continuous interaction between the eye, the nervous system, and the brain. When someone looks at an object, what he really sees is the light reflected from the object. This reflected light passes through the lens and falls on the retina of the eye. Here the light induces nerve impulses that travel through the optic nerve to the brain and then over other nerves to muscles and glands.
The eye is similar to a television camera. Both the eye and the television camera convert light energy to electrical energy. The eye converts light to nerve impulses that are interpreted by the brain as the sense perception called sight. A television camera converts light to electronic signals that are broadcast and transformed into light images in a television receiver. It is wonderful that human eyes blink an average of once every six seconds. This washes the eye with the salty secretion from the tear or lachrymal glands. Each tear gland is about the size and shape of an almond. These glands are situated behind the upper eyelid at the outer corner of the eye. After passing over the eye, the liquid from the gland is drained into the nose through the tear duct at the inner corner of the eye. What do we see when we look at an object?
Read the following passage carefully and choose the most appropriate answer to the question out of the four alternatives.
The human eye is a complex part of the body that is used for seeing. Eyes enable people to perform daily tasks and to learn about the world that surrounds them. Sight, or vision, is a rapidly occurring process that involves continuous interaction between the eye, the nervous system, and the brain. When someone looks at an object, what he really sees is the light reflected from the object. This reflected light passes through the lens and falls on the retina of the eye. Here the light induces nerve impulses that travel through the optic nerve to the brain and then over other nerves to muscles and glands.
The eye is similar to a television camera. Both the eye and the television camera convert light energy to electrical energy. The eye converts light to nerve impulses that are interpreted by the brain as the sense perception called sight. A television camera converts light to electronic signals that are broadcast and transformed into light images in a television receiver. It is wonderful that human eyes blink an average of once every six seconds. This washes the eye with the salty secretion from the tear or lachrymal glands. Each tear gland is about the size and shape of an almond. These glands are situated behind the upper eyelid at the outer corner of the eye. After passing over the eye, the liquid from the gland is drained into the nose through the tear duct at the inner corner of the eye. The eye is similar to the television camera because both
Read the following passage carefully and choose the most appropriate answer to the question out of the four alternatives.
The human eye is a complex part of the body that is used for seeing. Eyes enable people to perform daily tasks and to learn about the world that surrounds them. Sight, or vision, is a rapidly occurring process that involves continuous interaction between the eye, the nervous system, and the brain. When someone looks at an object, what he really sees is the light reflected from the object. This reflected light passes through the lens and falls on the retina of the eye. Here the light induces nerve impulses that travel through the optic nerve to the brain and then over other nerves to muscles and glands.
The eye is similar to a television camera. Both the eye and the television camera convert light energy to electrical energy. The eye converts light to nerve impulses that are interpreted by the brain as the sense perception called sight. A television camera converts light to electronic signals that are broadcast and transformed into light images in a television receiver. It is wonderful that human eyes blink an average of once every six seconds. This washes the eye with the salty secretion from the tear or lachrymal glands. Each tear gland is about the size and shape of an almond. These glands are situated behind the upper eyelid at the outer corner of the eye. After passing over the eye, the liquid from the gland is drained into the nose through the tear duct at the inner corner of the eye. The average rate of blinking of an eye is
Read the following passage carefully and choose the most appropriate answer to the question out of the four alternatives.
The human eye is a complex part of the body that is used for seeing. Eyes enable people to perform daily tasks and to learn about the world that surrounds them. Sight, or vision, is a rapidly occurring process that involves continuous interaction between the eye, the nervous system, and the brain. When someone looks at an object, what he really sees is the light reflected from the object. This reflected light passes through the lens and falls on the retina of the eye. Here the light induces nerve impulses that travel through the optic nerve to the brain and then over other nerves to muscles and glands.
The eye is similar to a television camera. Both the eye and the television camera convert light energy to electrical energy. The eye converts light to nerve impulses that are interpreted by the brain as the sense perception called sight. A television camera converts light to electronic signals that are broadcast and transformed into light images in a television receiver. It is wonderful that human eyes blink an average of once every six seconds. This washes the eye with the salty secretion from the tear or lachrymal glands. Each tear gland is about the size and shape of an almond. These glands are situated behind the upper eyelid at the outer corner of the eye. After passing over the eye, the liquid from the gland is drained into the nose through the tear duct at the inner corner of the eye. Lachrymal glands or tear glands are situated
একটি ধাতব তলে λ তরঙ্গদৈর্ঘ্যের একবর্ণী আলোকরশ্মি আপতিত হলে ফটো-ইলেক্ট্রন নির্গত হয় এবং এক্ষেত্রে বিভবের মান 3Vo একই তলে যখন 2λতরঙ্গদৈর্ঘ্যের একবর্ণী আলো আপতিত হয়, তখন নিবৃত্তি বিভবের মান Vol ফটো-ইলেক্ট্রন নির্গত হওয়ার জন্য ঐ তলটির সূচন তরঙ্গদৈর্ঘ্যের মান নির্ণয় কর।(A monochromatic light of wavelength λ is incident on a metallic surface then ejects photo-electron and the value of stopping potential is 3Vo. When the same surface is illuminated by a light of wavelength 2λ., the stopping potential becomes Vo. Calculate the threshold wavelength for this surface to eject photo electrons.)
Assertion (A): In the visible spectrum of light, red light is more energetic than green light.
Reason (R): The wavelength of red light is more than that of green light.
Consider the following statements.
1. Light of longer wavelength is scattered much more than the light of shorter wavelength.
2. The speed of visible light in water is 0.95 times the speed in vacuum.
3. Radio waves are produced by rapidly oscillating electrical currents.
4. To detect the overspeeding vehicles, police use the Doppler effect of reflected short radio waves.
Which of these statements are correct?
The wavelength at which DNA absorbs UV light is ___________