ICSE physics
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A short electric dipole (consists of two point charges +q and -q) is placed at the centre O and inside a large cube (ABCDEFGH) of length L, as shown in the figure below. The electric flux, remaining through the cube is:
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-
Zero
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-
B.
Zero
Since, it is an electric dipole, the net charge enclosed by the surface is zero. Therefore, according to Gauss's law, electric flux through the cube will be zero.
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The equivalent resistance between points a and f of the network as shown in the figure below is:
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24 ohm
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110 ohm
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140 ohm
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200 ohm
C.
140 ohm
A moving electron enters a uniform and perpendicular magnetic field. Inside the magnetic field, the electrons travels along,
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a straight line
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a parabola
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a circle
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a hyperbola
C.
a circle
A fish which is at a depth of 12 cm in water (
) is viewed by an observer on the bank of a lake. It's apparent depth as observed by the observer is:
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3 cm
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9 cm
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12 cm
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16 cm
B.
9 cm
Given,
Real depth of fish = 12 cm
Refractive Index = 4/3
Using the formula,
If EP and EK represent potential energy and kinetic energy respectively, of an orbital electron, then according to the Bohr's theory:
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Ek = -EP/2
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Ek = -EP
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Ek = -2EP
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Ek = 2 EP
A.
Ek = -EP/2
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Mock Test Series
Mock Test Series