Answer Key class 12 PT 2 Physics
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(a) 2e/𝞮0
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(b) remains stationary.
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(d) π : 4
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(d) 90°
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(b) 3J
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(C) both (A) and (B)
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(c)2:1
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(d) zero
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(b) 14.4 W
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(c) 0 to 1
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(c) 1 : 1
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(a)
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(b)
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(c)
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(d)
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(a) The oscillating charge produces electric field and oscillating electric field
produces
magnetic fields which is then produces an oscillating emf. A changing electric field
produces a
magnetic field produces and changing magnetic field produces a electric field, the
result is a wave of
electric and magnetic fields that can propagate through space. This propagating
field are called
EMW.
(b)
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Force on +q charge = + q E along
the direction of E
Force on –q charge = -q E
opposite to the direction of E
Net force on the dipole is F
Net = +qE- qE =0
But the two force act at different
point on the dipole. They form a
couple and exerts torque.
Torque = Force X perpendicular distance between lines
of action of forces. τ = qE X 2a Sin θ
τ = pE sin θ
Force on water drop due to electric field = Weight of water drop.
qE =mg E
= 6.125x1012N/C
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d2 < d1 for increasing field
and d2 = d1 for uniform field.
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Cu diamagnetic Al Para Iron ferro