Imagine that an object is falling through a long straight glass tube held vertical; air has been removed completely from the tube. The object does not touch the walls of the tube. Will the object experience any force of friction?
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When alpha particles are sent through a thin metal foil, most of them go straight through the foil because -
(C) most part of the atom is empty.
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2 g of lead, nitrate powder is taken in a boiling tube. The boiling tube is heated over a flame. Now answer the following :
(i) Brown fumes. white residue. (ii) Decomposition reaction 2Pb(NO3)2 →2PbO+4NO2+O2
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When you add about 2 ml of acetic acid to a test tube containing an equal amount of distilled water and leave the test-tube
When acetic acid and distilled water are mixed, they form a clear solution because acetic acid is completely miscible with water.
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Paheli saw the moon through a glass window at 8:00 p.m. She marked the position of the moon on the glass pane.
No, because the position of the moon keeps changing during the night.
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Paheli saw the moon through a glass window at 8:00 p.m. She marked the position of the moon on the glass pane.
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A magnifying glass is used, as the object to be viewed can be brought closer to the eye than the normal near point. This results in
(a), (b) (a) a larger angle to be subtended by the object at the eye and hence viewed in greater detail. (b) the formation of a virtual erect image.
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The angle of contact at the interface of water-glass is 0°, Ethylalcohol-glass is 0°,
The liquid in the trough is (c) mercury
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A 5 m 60 cm high vertical pole casts a shadow 3 m 20 cm long. Find at the same time −
(i) Let the length of the shadow of the other pole be x m. 1 m = 100 cm The given information in the form of a table is as follows. Height...
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A block of mass M is held against a rough vertical wall by pressing it with a finger. If the coefficient of friction between the block and the wall
If F is the force of the finger on the book, F = N, the normal reaction of the wall on the book. The minimum upward frictional force needed to...
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An object falling through a fluid is observed to have acceleration given by a = g – bv where g = gravitational acceleration and b is constant.
The value of constant speed, v = g/b
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