The drift velocity of electrons for a conductor connected in an electrical circuit is $V _{ d }$ The conductor in now replaced by another conductor with same material and same length but double the area of cross section The applied voltage remains same The new drift velocity of electrons will be
The drift velocity of electrons for a conductor connected in an electrical circuit is $V _{ d }$ The conductor in now replaced by another conductor with same material and same length but double the area of cross section The applied voltage remains same The new drift velocity of electrons will be
Show Hint
- $\frac{V_{ d }}{4}$
- $\frac{ V _{ d }}{2}$
- $2 V _{ d }$
- $V _{ d }$
The Correct Option is D
Solution and Explanation
\[ V_d = \frac{eE\tau}{m} \]
where \( e \) is the charge of the electron, \( E \) is the electric field, \( \tau \) is the relaxation time, and \( m \) is the mass of the electron. The drift velocity is independent of the area of cross-section of the conductor. Therefore, the new drift velocity will remain the same as \( V_d \).Top Questions on Speed and velocity
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Concepts Used:
Current Electricity
Current electricity is defined as the flow of electrons from one section of the circuit to another.
Types of Current Electricity
There are two types of current electricity as follows:
Direct Current
The current electricity whose direction remains the same is known as direct current. Direct current is defined by the constant flow of electrons from a region of high electron density to a region of low electron density. DC is used in many household appliances and applications that involve a battery.
Alternating Current
The current electricity that is bidirectional and keeps changing the direction of the charge flow is known as alternating current. The bi-directionality is caused by a sinusoidally varying current and voltage that reverses directions, creating a periodic back-and-forth motion for the current. The electrical outlets at our homes and industries are supplied with alternating current.