A smart phone charger delivers charge to the phone, in the form of electrons, at a rate of -0.75. How many electrons are delivered to the phone during 27 min of charging?

Respuesta :

Answer:

The no. of electrons is [tex]7.59\times 10^{21}[/tex]

Solution:

According to the question:

The rate at which the charge is delivered is given by:

[tex]\frac{dQ}{dt} = - 0.75[/tex]

Now,

[tex]\int_{0}^{Q}dQ = - 0.75\int_{0}^{27 min} dt[/tex]

[tex]Q = -0.75t|_{0}^{27 min}[/tex]

[tex]Q= -0.75\times 27\times 60 = - 1215 C[/tex]

No. of electrons, n can be calculated from the following relation:

Q = ne

where

e = electronic charge =[tex]1.6\times 10^{- 19} C[/tex]

Thus

[tex]n = \frac{Q}{e}[/tex]

[tex]n= \frac{1215}{1.6\times 10^{- 19}}[/tex]

[tex]n = 7.59\times 10^{21}[/tex]