AP EAMCET202021 Sep 2020Morning ShiftPhysicsCurrent ElectricityActual
A copper wire of radius (0.1 ~mm ) and resistance (2 k ) is connected across a power supply of (40 ~V ). The number of electrons transferred per second between the supply and the wire at one end is
Options
- A(2.00 10¹⁶ )
- B(1.25 10¹⁷ )
- C(2.85 10¹⁷ )
- D(3.25 10¹⁶ )
Correct answer
B. (1.25 10¹⁷ )
Step-by-step solution
Radius of copper wire, (r=0.1 ~mm ) (=1 10⁻⁴ ~m ) Resistance, (R=2 k =2 10^3 ) Power supply, (V=40 ~V ) Current flowing through the wire, (I= V R = 40 2 10^3 =2 10⁻² ~A ) ( ) Charge flowing per second (q=I t=2 10⁻² 1=2 10⁻² C ) ( ) Number of electrons transferred, ( aligned n & = q e = 2 10⁻² 1.6 10⁻¹⁹ & =1.25 10¹⁷ electrons aligned )