Respuesta :
Answer:
The number of electrons is [tex]6.3\times10^{21}\ electrons[/tex]
(D) is correct option.
Explanation:
Given that,
Battery capacity = 750 mA-h
Time t= 8 hours
Time t'=3 hours
We need to calculate the battery capacity
[tex]Battery\ capacity=750\times10^{-3}\times3600[/tex]
[tex]Battery\ capacity=2700\ A-s[/tex]
We need to calculate the number of electrons in 1 C Li
Using formula for number of electron
[tex]n=\dfrac{1}{e}[/tex]
[tex]n=\dfrac{1}{1.6\times10^{-19}}[/tex]
[tex]n=6.25\times10^{18}\ electrons[/tex]
We need to calculate the number of electron in 2700 C
[tex]2700\ C=2700\times6.25\times10^{18}=1.68\times10^{22}\ electrons[/tex]
The total number of electrons battery can deliver in 8 hours
[tex]n=1.68\times10^{22}\ electrons[/tex]
We need to calculate the number of electron in 3 hours
Using formula of number of electrons
[tex]n=\dfrac{n\times t'}{t}[/tex]
Put the value into the formula
[tex]n=\dfrac{1.68\times10^{22}\times3}{8}[/tex]
[tex]n=6.3\times10^{21}\ electrons[/tex]
Hence, The number of electrons is [tex]6.3\times10^{21}\ electrons[/tex]
Answer:
option (D)
Explanation:
capacity, q = 750 mA - h = 0.750 x 3600 A-s = 2700 C
time, t = 3 hours = 3 x 3600 seconds = 10800 s
1 C = 6.24 x 10^18 electrons
So, 2700 C = 2700 x 6.24 x 10^18 electrons
= 1.684 x 10^22 electrons
but it is used for 3/8 th part
so, number of electrons = 3/8 x 1.684 x 10^22
= 6.315 x 10^21 electrons
