151792
If $E$ denotes electric field in a uniform conductor and $v_{d}$ the corresponding drift velocity of free electrons in the conductor, then, which of these is correct?
1
2
3
4
Explanation:
A We know that, $\mathrm{v}_{\mathrm{d}}=-\frac{\mathrm{eE}}{\mathrm{m}} \tau$ $\because \quad \mathrm{v}_{\mathrm{d}} \propto \mathrm{E}$ Hence, option (a) is correct.
SRMJEEE - 2008
Current Electricity
151798
When a long straight uniform rod is connected across an ideal cell, the drift velocity of electrons in it is $v$. If a uniform hole is made along the axis of the rod and the same battery is used, then the drift velocity of electrons becomes
1 $\mathrm{v}$
2 $>$ v
3 $\lt$ v
4 zero
Explanation:
A Given, Drift velocity $\left(\mathrm{v}_{\mathrm{d}}\right)=\mathrm{v}$ We know that, Current, $\mathrm{I}=\mathrm{neAv}_{\mathrm{d}}$ $\mathrm{I}=\mathrm{neAv}$ $\frac{\mathrm{V}}{\mathrm{R}}=$ neAv $\frac{\mathrm{V}}{\rho \frac{l}{\mathrm{~A}}}=\mathrm{neAv}$ $\left[\because \mathrm{R}=\frac{\rho l}{\mathrm{~A}}\right]$ $\frac{\mathrm{VA}}{\rho l}=\mathrm{neAv}$ $\mathrm{v}=\frac{\mathrm{V}}{\rho \ln \mathrm{e}}$ So, drift velocity is not depends on cross section area. Hence, if a uniform hole is made along the axis of rod then drift velocity of electrons becomes same (v).
AP EAMCET -2016
Current Electricity
151803
The main power supply in India is at $220 \mathrm{~V}$, whereas that in the US is at $110 \mathrm{~V}$. Which one among the following statements in this regard is correct?
1 $110 \mathrm{~V}$ is safer but more expensive to maintain
2 $110 \mathrm{~V}$ is safer and cheaper to maintain
3 $110 \mathrm{~V}$ ads to lower power loss
4 $110 \mathrm{~V}$ works better at higher latitudes
Explanation:
A By Ohm's law, $\mathrm{V}=\mathrm{IR}$ As potential will be high then less heat will be generated so it would be expensive less and when potential will lower the heat will be generated more so it will more expensive. So, $110 \mathrm{~V}$ is safer but more expensive compared to $220 \mathrm{~V}$.
151792
If $E$ denotes electric field in a uniform conductor and $v_{d}$ the corresponding drift velocity of free electrons in the conductor, then, which of these is correct?
1
2
3
4
Explanation:
A We know that, $\mathrm{v}_{\mathrm{d}}=-\frac{\mathrm{eE}}{\mathrm{m}} \tau$ $\because \quad \mathrm{v}_{\mathrm{d}} \propto \mathrm{E}$ Hence, option (a) is correct.
SRMJEEE - 2008
Current Electricity
151798
When a long straight uniform rod is connected across an ideal cell, the drift velocity of electrons in it is $v$. If a uniform hole is made along the axis of the rod and the same battery is used, then the drift velocity of electrons becomes
1 $\mathrm{v}$
2 $>$ v
3 $\lt$ v
4 zero
Explanation:
A Given, Drift velocity $\left(\mathrm{v}_{\mathrm{d}}\right)=\mathrm{v}$ We know that, Current, $\mathrm{I}=\mathrm{neAv}_{\mathrm{d}}$ $\mathrm{I}=\mathrm{neAv}$ $\frac{\mathrm{V}}{\mathrm{R}}=$ neAv $\frac{\mathrm{V}}{\rho \frac{l}{\mathrm{~A}}}=\mathrm{neAv}$ $\left[\because \mathrm{R}=\frac{\rho l}{\mathrm{~A}}\right]$ $\frac{\mathrm{VA}}{\rho l}=\mathrm{neAv}$ $\mathrm{v}=\frac{\mathrm{V}}{\rho \ln \mathrm{e}}$ So, drift velocity is not depends on cross section area. Hence, if a uniform hole is made along the axis of rod then drift velocity of electrons becomes same (v).
AP EAMCET -2016
Current Electricity
151803
The main power supply in India is at $220 \mathrm{~V}$, whereas that in the US is at $110 \mathrm{~V}$. Which one among the following statements in this regard is correct?
1 $110 \mathrm{~V}$ is safer but more expensive to maintain
2 $110 \mathrm{~V}$ is safer and cheaper to maintain
3 $110 \mathrm{~V}$ ads to lower power loss
4 $110 \mathrm{~V}$ works better at higher latitudes
Explanation:
A By Ohm's law, $\mathrm{V}=\mathrm{IR}$ As potential will be high then less heat will be generated so it would be expensive less and when potential will lower the heat will be generated more so it will more expensive. So, $110 \mathrm{~V}$ is safer but more expensive compared to $220 \mathrm{~V}$.
151792
If $E$ denotes electric field in a uniform conductor and $v_{d}$ the corresponding drift velocity of free electrons in the conductor, then, which of these is correct?
1
2
3
4
Explanation:
A We know that, $\mathrm{v}_{\mathrm{d}}=-\frac{\mathrm{eE}}{\mathrm{m}} \tau$ $\because \quad \mathrm{v}_{\mathrm{d}} \propto \mathrm{E}$ Hence, option (a) is correct.
SRMJEEE - 2008
Current Electricity
151798
When a long straight uniform rod is connected across an ideal cell, the drift velocity of electrons in it is $v$. If a uniform hole is made along the axis of the rod and the same battery is used, then the drift velocity of electrons becomes
1 $\mathrm{v}$
2 $>$ v
3 $\lt$ v
4 zero
Explanation:
A Given, Drift velocity $\left(\mathrm{v}_{\mathrm{d}}\right)=\mathrm{v}$ We know that, Current, $\mathrm{I}=\mathrm{neAv}_{\mathrm{d}}$ $\mathrm{I}=\mathrm{neAv}$ $\frac{\mathrm{V}}{\mathrm{R}}=$ neAv $\frac{\mathrm{V}}{\rho \frac{l}{\mathrm{~A}}}=\mathrm{neAv}$ $\left[\because \mathrm{R}=\frac{\rho l}{\mathrm{~A}}\right]$ $\frac{\mathrm{VA}}{\rho l}=\mathrm{neAv}$ $\mathrm{v}=\frac{\mathrm{V}}{\rho \ln \mathrm{e}}$ So, drift velocity is not depends on cross section area. Hence, if a uniform hole is made along the axis of rod then drift velocity of electrons becomes same (v).
AP EAMCET -2016
Current Electricity
151803
The main power supply in India is at $220 \mathrm{~V}$, whereas that in the US is at $110 \mathrm{~V}$. Which one among the following statements in this regard is correct?
1 $110 \mathrm{~V}$ is safer but more expensive to maintain
2 $110 \mathrm{~V}$ is safer and cheaper to maintain
3 $110 \mathrm{~V}$ ads to lower power loss
4 $110 \mathrm{~V}$ works better at higher latitudes
Explanation:
A By Ohm's law, $\mathrm{V}=\mathrm{IR}$ As potential will be high then less heat will be generated so it would be expensive less and when potential will lower the heat will be generated more so it will more expensive. So, $110 \mathrm{~V}$ is safer but more expensive compared to $220 \mathrm{~V}$.
151792
If $E$ denotes electric field in a uniform conductor and $v_{d}$ the corresponding drift velocity of free electrons in the conductor, then, which of these is correct?
1
2
3
4
Explanation:
A We know that, $\mathrm{v}_{\mathrm{d}}=-\frac{\mathrm{eE}}{\mathrm{m}} \tau$ $\because \quad \mathrm{v}_{\mathrm{d}} \propto \mathrm{E}$ Hence, option (a) is correct.
SRMJEEE - 2008
Current Electricity
151798
When a long straight uniform rod is connected across an ideal cell, the drift velocity of electrons in it is $v$. If a uniform hole is made along the axis of the rod and the same battery is used, then the drift velocity of electrons becomes
1 $\mathrm{v}$
2 $>$ v
3 $\lt$ v
4 zero
Explanation:
A Given, Drift velocity $\left(\mathrm{v}_{\mathrm{d}}\right)=\mathrm{v}$ We know that, Current, $\mathrm{I}=\mathrm{neAv}_{\mathrm{d}}$ $\mathrm{I}=\mathrm{neAv}$ $\frac{\mathrm{V}}{\mathrm{R}}=$ neAv $\frac{\mathrm{V}}{\rho \frac{l}{\mathrm{~A}}}=\mathrm{neAv}$ $\left[\because \mathrm{R}=\frac{\rho l}{\mathrm{~A}}\right]$ $\frac{\mathrm{VA}}{\rho l}=\mathrm{neAv}$ $\mathrm{v}=\frac{\mathrm{V}}{\rho \ln \mathrm{e}}$ So, drift velocity is not depends on cross section area. Hence, if a uniform hole is made along the axis of rod then drift velocity of electrons becomes same (v).
AP EAMCET -2016
Current Electricity
151803
The main power supply in India is at $220 \mathrm{~V}$, whereas that in the US is at $110 \mathrm{~V}$. Which one among the following statements in this regard is correct?
1 $110 \mathrm{~V}$ is safer but more expensive to maintain
2 $110 \mathrm{~V}$ is safer and cheaper to maintain
3 $110 \mathrm{~V}$ ads to lower power loss
4 $110 \mathrm{~V}$ works better at higher latitudes
Explanation:
A By Ohm's law, $\mathrm{V}=\mathrm{IR}$ As potential will be high then less heat will be generated so it would be expensive less and when potential will lower the heat will be generated more so it will more expensive. So, $110 \mathrm{~V}$ is safer but more expensive compared to $220 \mathrm{~V}$.
