Question:
The order of the electric field required to pull out electrons from a metal by field emission (in $Vm^{-1}$) is
The order of the electric field required to pull out electrons from a metal by field emission (in $Vm^{-1}$) is
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Field emission happens only under extremely strong electric fields.
Updated On: Apr 24, 2026
- $10^2$
- $10^8$
- $10^5$
- $10^6$
- $10^4$
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The Correct Option is B
Solution and Explanation
Concept:
• Field emission requires very strong electric fields
Step 1: Typical value
Field emission occurs at extremely high electric fields of order: \[ 10^8 \, Vm^{-1} \] Final Conclusion:
Option (B)
• Field emission requires very strong electric fields
Step 1: Typical value
Field emission occurs at extremely high electric fields of order: \[ 10^8 \, Vm^{-1} \] Final Conclusion:
Option (B)
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