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प्रश्न
The potential difference applied across a given conductor is doubled. How will this affect (i) the mobility of electrons and (ii) the current density in the conductor? Justify your answers.
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उत्तर
Mobility of electron `mu = (v_d)/E = (v_dl)/V`
as `E = V/l`
Hence, `mu prop 1/V`
If V becomes 2V, the mobility will become half. The current density is given by
`J = n ev_d`
J = `n e.(eVtau)/(ml)`
J = `(n e^2Vtau)/(ml)`
J ∝ V
When V become 2V current density will become twice.
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संबंधित प्रश्न
(a) drift speed
(b) current density
(c) electric current
(d) electric field
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Consider the following statements.
(A) Free-electron density is different in different metals.
(B) Free-electron density in a metal depends on temperature.
Thomson Effect is caused _______________ .
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- Consider circuit in figure. How much energy is absorbed by electrons from the initial state of no current (ignore thermal motion) to the state of drift velocity?
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Based on this, answer the following:
- How does the drift velocity change with a change in the potential difference across the conductor?
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