Question

The current flowing into the collector lead of a certain bipolar junction transistor (BJT) is measured to be 1 nA. If no charge was transferred in or out of the collector lead prior to t = 0, and the current flows for 1 min. calculate the total charge which crosses into the collector.

Answer 1

the total charge which crosses into the collector is 60 nC

Step-by-step explanation:

Given the data in the question;

current flowing into the collector lead of the bipolar junction transistor (BJT); i = 1 nA = 10⁻⁹ A

no charge was transferred in or out of the collector lead prior to t = 0

the current flow time t = 1 min = 60 sec

Now we write the relation between current, charge, and time;

i = dq / dt

where i is current, q is charge and t is time. { d refers to change }

Now,

`q=\int\limits^t_(t=0) {i(t)} \, dt`

`q=\int\limits^(t=60)_(t=0) { (10^(-9)) } \, dt`

`q = ( 10^(-9)) (t)_0^{60`

`q = ( 10^(-9)) ( 60 - 0 )`

q = 60 × 10⁻⁹ C

q = 60 nC

Therefore, the total charge which crosses into the collector is 60 nC