Question

What is the current in milliamperes produced by the solar cells of a pocket calculator through which 4.00 C of charge passes in 4.00 h?

a) 1.00 mA
b) 0.25 mA
c) 0.50 mA
d) 2.00 mA

Answer 1

The current produced by the solar cells of a pocket calculator when 4.00 C of charge passes in 4.00 h is 0.25 mA. This is calculated by converting the time to seconds and using the current formula I = Q/t.

Step-by-step explanation:

To find the current in milliamperes produced by the solar cells of a pocket calculator when 4.00 C of charge passes through it in 4.00 hours (h), we use the definition of current, which is the rate of flow of electric charge. Current (I) is calculated using the formula I = Q/t, where Q is the charge in coulombs and t is the time in seconds.

First, we need to convert hours to seconds to use in the formula:

• 4.00 hours = 4.00 × 3600 seconds = 14400 seconds

Now we can calculate the current:

• I = 4.00 C / 14400 s = 0.000277778 C/s

Since 1 A = 1 C/s, we convert the current to milliamperes (mA) by multiplying by 1000:

• 0.000277778 C/s × 1000 = 0.277778 mA

This is closest to choice (b) 0.25 mA, which is the correct answer.