A lens forms an erect, magnified, and virtual image of an object. Name the device which uses this principle.
[5] Refraction Through a Lens
Chapter: [5] Refraction Through a Lens
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What is a magnifying glass?
[5] Refraction Through a Lens
Chapter: [5] Refraction Through a Lens
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Draw a neat labelled ray diagram to show the formation of an image by a magnifying glass. State three characteristics of the image.
[5] Refraction Through a Lens
Chapter: [5] Refraction Through a Lens
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Where is the object placed with respect to the principal focus of a magnifying glass, so as to see its enlarged image? Where is the image obtained?
[5] Refraction Through a Lens
Chapter: [5] Refraction Through a Lens
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Define magnifying power of a simple microscope. How can it be increased?
[5] Refraction Through a Lens
Chapter: [5] Refraction Through a Lens
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A magnifying glass forms ______.
[5] Refraction Through a Lens
Chapter: [5] Refraction Through a Lens
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Ray diagram for the formation of image by a magnifying glass.
[5] Refraction Through a Lens
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What is electrical resistance? Write its SI unit.
[8] Current Electricity
Chapter: [8] Current Electricity
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Name the physical quantity that represents the ratio of potential difference and current.
[8] Current Electricity
Chapter: [8] Current Electricity
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What do you mean by an equivalent resistance?
[8] Current Electricity
Chapter: [8] Current Electricity
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A graph is plotted taking p.d. along y-axis and electric current along x-axis. Name the physical quantity that represents the slope of this graph (Fig.).
[8] Current Electricity
Chapter: [8] Current Electricity
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Define resistivity of a metal.
[8] Current Electricity
Chapter: [8] Current Electricity
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What are the SI units of specific resistance?
[8] Current Electricity
Chapter: [8] Current Electricity
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Name the following substances:
(i) Showing low resistivity,
(ii) Showing very high resistivity,
(iii) Showing moderate resistivity.
[8] Current Electricity
Chapter: [8] Current Electricity
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Does an ammeter have a low or high resistance?
[8] Current Electricity
Chapter: [8] Current Electricity
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Does a voltmeter have a low or high resistance?
[8] Current Electricity
Chapter: [8] Current Electricity
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What do you mean by a rheostat?
[8] Current Electricity
Chapter: [8] Current Electricity
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Potential difference between two points of a wire carrying 2 ampere current is 0.1 volt. Calculate the resistance between these points.
[8] Current Electricity
Chapter: [8] Current Electricity
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The potential difference between the terminals of an electric iron is 240 V and the current flowing through it is 6 A. What is the resistance of the electric iron?
[8] Current Electricity
Chapter: [8] Current Electricity
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What potential difference is needed to drive a current o f 1 A through a 5 Ω resistor?
[8] Current Electricity
Chapter: [8] Current Electricity
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