Question
An AC source is connected to a diode and a resistor in series. Is the current thorough the resistor AC or DC?

Answer

If the diode and resistor are in series, for the positive half cycle of AC, the current through the resistor will be DC. But for the next half cycle the current through the resistor will be zero. As a diode is a device that converts AC into DC, current through the resistor will be DC.

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Read the passage given below and answer the following questions from 1 to 5. Projectile motion is a form of motion in which an object or particle is thrown with some initial velocity near the earth’s surface and it moves along a curved path under the action of gravity alone. The path followed by a projectile is called its trajectory, which is shown below. When a projectile is projected obliquely, then its trajectory is as shown in the figure below. Here velocity u is resolved into two components, we get (a) u cosθ along OX and (b) u sinθ along OY.
  1. The example of such type of motion is:
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  2. Motion of boat in sea.
  3. A javelin thrown by an athlete.
  4. Motion of ball thrown vertically upward.
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  2. Decreasing
  3. Increasing
  4. Zero
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  2. 3.0s
  3. 4.0s
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  2. $[ML^{-1} T^{-2}]$
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