Tag: generation of electricity
Questions Related to generation of electricity
The reflector on top of solar cooker is used to:
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diverge solar energy
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focus solar energy
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focus light energy
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reflect excess energy to surroundings
The reflector on the top of the solar cooker is used to focus the solar energy over the glass surface. The mirror reflects the heat energy in a confined area and increases the net input energy to the solar cooker.
The semiconductor panel on the front of a scientific calculator is
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Electric Cell
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Solar Cell
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Plane mirror
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Convex mirror
Solar cells are fitted on a scientific calculator.
Solar cell production is
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increasing slowly
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increasing exponentially
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constant
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decreasing
Production of solar cells is increasing exponentially every year.
What is the principle of working of solar cell
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photovoltaic effect
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green house effect
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Archimedes' principle
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Faraday's law
Solar cell works on the principle of photovoltaic effect according to which free electrons are produced when light of certain wavelength is incident on semiconductors.
The reflector on top of solar cooker is adjustable because of:
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revolution of Earth about Sun.
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rotation of Earth about Sun.
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atmospheric profile of gases.
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density variation in atmosphere.
Rotation of Earth about the Sun causes the position of Sun to change during the day. Hence, the mirror on the top of the solar cooker needs adjusting during the day to focus the rays in a small area.
A solar cooker works on:
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electrical energy
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magnetic energy
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solar energy
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chemical energy
Solar cooker is a device used to collect the solar energy in the form of heat.
Which of the following will improve the efficiency of a solar cooker?
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Regularly orienting the solar cooker according to the Sun.
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Increasing the span of glass sheet on the top.
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Using black coated utensils.
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All of the above.
To improve the efficiency of a solar cooker, the following steps need to be done:
What is solar cooker?
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Device which uses energy of direct sunlight to cook food
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Device which uses energy of direct falling water to cook food
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Device which uses energy of direct wind to cook food
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Device which uses energy of direct thermal energy to cook food
Solar cooker is a device that uses energy from the Sun directly to cook food or warm fluids.
How heat is generated in solar cooker to cook food?
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Light reflected from plane mirror concentrates solar energy inside solar cooker
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Light refracted from plane mirror concentrates solar energy inside solar cooker
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Light deflected from plane mirror concentrates solar energy inside solar cooker
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none
Concave or plain mirror are used on the top cover of the cooker. Light get reflected from these mirrors, these mirrors concentrates the light onto a point or a region where the food is kept to be cooked.
What is fixed at the top of solar cooker?
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Plane mirror or concave mirror
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Convex mirror
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bifocal mirror
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Cylindrical mirror
Concave or plain mirror is used in the solar cooker in order to concentrate the sunlight at one spot.