Hans Christian Oersted observed that a current-carrying wire deflects a compass needle, demonstrating the magnetic effect of current.
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15. The period of oscillation of a magnet in a vibration magnetometer is 2 seconds. The period of oscillation of a magnet whose magnetic moment is four times that of the first magnet is
The quantity qvB has dimensions of force, whose SI unit is the newton.
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The capacitor of 1 μF is charged to 100 V and then disconnected from the power supply. Another uncharged capacitor of 4 μF is now connected across it. The common voltage across the combination would be
A cathode-ray oscilloscope displays electrical waveforms (voltage vs time), so option A best describes its primary use.
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A ball of mass 1 g and charge 10^-8 C moves from a point A whose potential is 600 V to the point B whose potential is zero. Velocity of the ball at the point B is 20 cm s^-1. The velocity of the ball at the point A is
An electroscope is the classic instrument used to detect and give a measure of electric charge via leaf divergence.
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Six identical capacitors each of 1 µF are joined in parallel and the combination is put across a battery of emf 2 volt. Now the battery is disconnected and the capacitors are joined in series. The total energy and potential difference across the series combination is
Initial energy = 1/2 * (6 µF) * (2 V)^2 = 12 µJ; when reconnected in series preserving the charge on each, voltages add to 6×2 V = 12 V, so energy remains 12 µJ and total voltage is 12 V.
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As a positively charged rod is brought closer and closer to a positively charged electroscope, the gold leaf
