Question

1 x 10^5 electrons pass from a point P towards another point Q in a conductor in 10^-4 seconds. Find the current.​

Answer 1

Given:

No. of electrons passing from pt. P to pt. Q,n= 10⁵

Time taken by electrons, t=10⁻⁴s

To Find:

Current produced

Solution:

We know that,

• According to quantisation of charge

$\pink{\underline{\boxed{\bf{Q=ne}}}}$

• Relation between current, charge and time is given by

$\pink{\underline{\boxed{\bf{I=\dfrac{Q}{t}}}}}$

where,

Q is charge

n is no. of electrons

e is magnitude of charge on electron i.e. 1.6×10⁻¹⁹C

I is current

t is time taken

$\rule{190}{1}$

Let the charge on given electrons be Q

So,

$\longrightarrow\rm{Q=ne}$

$\longrightarrow\rm{Q=10^{5}\times1.6\times10^{-19}}$

$\longrightarrow\rm{Q=1.6\times10^{-14}\ C}$

Now, let the current produced be I

So,

$\longrightarrow\rm{I=\dfrac{Q}{t}}$

$\longrightarrow\rm{I=\dfrac{1.6\times10^{-14}}{10^{-4}}}$

$\longrightarrow\rm\green{I=1.6\times10^{-10}\ A}$

Hence, the current produced is 1.6×10⁻¹⁰A.