Question

A current of 20 A flows in a wire for 30 seconds.
Find the amount of charge and the number of free
electrons transferred through the wire
Ans. 6 10 C, 3.75 1015​

Answer 1

Answer:

600 c of charge and 6.25*600 free electrones

Answer 2

Answer:

$\bigstar{\bold{Charge=600\:C}}$

$\bigstar{\bold{Number\:of\:electrons=3.75\times 10^{21} }}$

Explanation:

$\Large{\underline{\underline{\sf{Given:}}}}$

• Current (I) = 20 A
• Time taken (t) = 30 s

$\Large{\underline{\underline{\sf{To\:Find:}}}}$

• Amount of charge (q)
• Number of electrons (e)

$\Large{\underline{\underline{\sf{Solution:}}}}$

→ The charge of a conductor is given by the formula,

  q = I × t

  where q is the charge, I is the current and t is the time.

→ Substituting the datas we get,

  q = 20 × 30

  q = 600 C

→ Hence the charge on the conductor is 600 C

  $\boxed{\bold{Charge=600\:C}}$

→ Now we have to find the number of electrons flowing through the conductor.

→ By quantization of charges we know that

  q = n e

 where q is the charge, n is the number of electrons, and e = 1.6 × 10⁻¹⁹C

→ Substitute the datas,

  600 = n × 1.6 × 10⁻¹⁹

  n = 600/1.6 × 10⁻¹⁹

  n = 375 × 10¹⁹

  n = 3.75 × 10²¹ electrons

$\boxed{\bold{Number\:of\:electrons=3.75\times 10^{21} }}$

$\Large{\underline{\underline{\sf{Notes:}}}}$

→ Quantization is a basic property of electric charge.

→ It state that charge is always an integral multiple of e

  q = n e