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The following table gives the length of ...

The following table gives the length of three copper rods, their diameters, and the potential differences between their ends. Rank the rods according to (a) the magnitude of the electric field within them, (b) the current density within them, and (c ) the drift speed of electrons through them, greates first.

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a. `E_1= (V)/(L), E_2 = (2)/(2L) = (V)/(L), E_3 = (2V)/(3L)`.
Hecne, `E_1 =E_2 gt E_3`
c. `V_d prop E`. Hence, `V_(d_1) = V_(d_2) gtV_(d_3)`
b. `I = "ne"Av_d = (nepid^2)/(4) = v_d = (mepi)/(4)v_dd^2`
or `I prop v_dd^2 or I prop Ed^2 or I = Ked^2`
`I_1= (KV)/(L)(3d)^2 = (9Kvd^2)/(L), I_2 = K(V)/(L)d^2A`
`I_3 = K(2V)/(3L)(2d)^2 = (8KV d^2)/(3L)`
Hence,`I_1gt I_3gtI_2.`
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CENGAGE PHYSICS ENGLISH-ELECTRIC CURRENT AND CIRCUIT-Exercise 5.1
  1. Though the drift velocity of electorn responsible for current in a con...

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  2. a. A steady current flows in a metallic conductor of non - uniform cro...

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  3. A potential difference V is applied to copper wire of diameter d and l...

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  4. A wire has a resistance R. What will be its resistace if (a) it is d...

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  5. The current in a wire varies with time according to the equation I = ...

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  6. The following table gives the length of three copper rods, their diame...

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  7. The current voltage graphs for a given metalic wire two different temp...

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  8. The voltage-current variations of two metallic wire X and Y at constan...

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  9. A beam contains 2.0xx10^8 doubly charged positive ions per cubic centi...

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  10. The current density across a cylindrical conductor of radius R varies ...

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  11. Shown a conductor of length l having a circular cross section. The rad...

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  12. If a copper wire is stretched to make it 0.1% longer what is the perce...

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  13. A copper wire having cross- sectional area of 0.5 mm^2 and a length of...

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  14. A copper wire having cross- sectional area of 0.5 mm^2 and a length of...

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  15. A conductive wire has resistance of 10 ohm at 0^@C and alpha is 1/273^...

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  16. What is the drift speed of the conduction electrons in a copper wire w...

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  17. (a) At what temperature would the resistance of a copper conductor be ...

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  18. A potential difference is applied across the filament of a bulb at t =...

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  19. The space between the plates orf a parallel plate capacitor is complet...

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  20. A uniform copper wire of mass 2.23 xx10^(-3) kg carries a current of ...

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