Final answer:
To form a charge of -3 nC, approximately 1.88×1010 electrons are needed, calculated by dividing the total charge by the charge of a single electron.
Step-by-step explanation:
To determine how many electrons are needed to form a charge of -3 nC, we can use the relationship that the number of electrons, ne, is equal to the total charge divided by the charge per electron. Given that 1 nC (nanocoulomb) is 1×10-9 C (coulombs) and the charge of one electron is approximately -1.60×10-19 C, we perform the following calculation:
ne = × (-3×10-9 C) / (-1.60×10-19 C/e-)
This yields:
ne = 18.75×1010 electrons, which is approximately 1.88×1010 electrons. Therefore, roughly 1.88×1010 electrons are required to produce a charge of -3 nC.