Question

a potential of 3v is applied across a conductor of resistance 1.5.calculate the number of electron flowing through it in one second. charge of electron e=1.6×10–19

Answer 1

it is correct answer

Answer 2

Given :

Potential difference (V) = 3 V

Resistance (R) = 1.5 ohm

To Find :

Number of electron flowing through the conductor in one second

Solution :

According to Ohm's Law, Current flowing through a conductor is directly proportional to the potential difference between its two ends.

    Current (I)  ∝ Potential (V)

⇒                V = IR

⇒                I  = $\frac{V}{R}$

where, V = potential difference; I = Current; R = resistance

∴ The current flowing through the conductor (I) = $\frac{3}{1.5}$ = 2 A

Charge (Q) = Current (I) × Time (T)

                  =  2 × 1

                  = 2 C

We know,

  Charge (Q) = No. of electrons (n) × Charge of the electron (e)

⇒     2            =   n × 1.6 × 10⁻¹⁹

⇒      n            =  $\frac{2}{1.6 * 10^-^1^9}$

∴       n            =  1.25 × 10¹⁹

Hence, the number of electrons flowing through the conductor in one second is 1.25 × 10¹⁹