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A flat coil of wire rotates at a constant speed about an axis perpendicular to a uniform magnetic field. Draw a graph to show how the induced e.m.f. varies relative to the positions of the coil during its one complete rotation. At what position of the coil, the e.m.f. has the maximum value?
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State change that you would make to convert an A.C. generator into a D.C. generator. Illustrate the change by a diagram.
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The given figures 1 to 3 show the working of a simple A.C. generator. Study the diagrams and answers of the following questions.



(i) State and explain the principle underlying the working of a simple generator.
(ii) Where is the loop of wire placed?
(iii) What happens when the loop is rotated?
(iv) Indicate the direction of the current flow through the wire for the first half of the turn (in first figure). Name and state the rule used in finding the direction of the current.
(v) Indicate the direction of the current for the case shown in second figure.
(vi) Indicate the direction of current in the outer circuit (i.e., electric bulb) in first and third figure.
(vii) What type of current is shown in the above diagrams? Explain.
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Suggest one effective way for the safe disposal of nuclear waste.
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Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the ______.
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Which characteristic of sound is affected due to the larger surface of a school bell?
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How can one stop the radiations escaping from a nuclear reactor in a nuclear power plant?
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State one factor that affects the magnitude of induced current in an AC generator.
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An endoscope uses optic fiber to transmit high resolution images of internal organs without loss of information. The principle of light that is used by the optic fiber is based on ______.
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The diagram below shows a fish in the tank and its image seen on the surface of the water.

Name the phenomenon responsible for the formation of this image.
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State two differences between normal reflection and total internal reflection.
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Explain the motion of a planet around the sun in an elliptical path.
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Name the type of energy (kinetic energy K or potential energy U) possessed in the following case:
A moving cricket ball
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Name the type of energy (kinetic energy K or potential energy U) possessed in the following case:
A compressed spring
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Name the type of energy (kinetic energy K or potential energy U) possessed in the following case:
A moving bus
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Two resistors having resistance 8 Ω and 12 Ω are connected in parallel. Find their equivalent resistance.
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Four resistors each of resistance 5 Ω are connected in parallel. What is the effective resistance?
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You have three resistors of values 2 Ω, 3 Ω, and 5 Ω. How will you join them so that the total resistance is less than 1 Ω? Draw a diagram and find the total resistance.
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Two resistors of resistances 2 Ω and 3 Ω are connected in parallel to a cell to draw current 0.5 A from the cell. Draw a labelled diagram of the arrangement
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Two resistors of resistance 2 Ω and 3 Ω are connected in parallel to a cell to draw current 0.5 A from the cell. Calculate the current in each resistor.
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