COMEDK · Physics · 19. Current Electricity
Two wires A and B made of same material having length 10 cm and 40 cm respectively are connected in parallel to the same source of emf 10 V . What will be the ratio of the drift velocity of the electrons in the wire \(A\) to the drift velocity in the wire \(B\) ?
- A \(\dfrac{V_{d A}}{V_{d B}}=1: 2\)
- B \(\dfrac{V_{d A}}{V_{d B}}=4: 1\)
- C \(\dfrac{V_{d A}}{V_{d B}}=2: 1\)
- D \(\dfrac{V_{d A}}{V_{d B}}=1: 4\)
Answer & Solution
Correct Answer
(B) \(\dfrac{V_{d A}}{V_{d B}}=4: 1\)
Step-by-step Solution
Detailed explanation
The drift velocity \(v_{d}\) of electrons in a conductor is given by the formula \(v_{d} = \dfrac{I}{neA}\), where \(I\) is the current, \(n\) is the electron density, \(e\) is the elementary charge, and \(A\) is the cross-sectional area. Since the wires are made of the same…
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