Q. What is the total charge in coulomb of 75.0 kg of electrons?
A) $0.32 \times 10^{13}C$
B) $3.2 \times 10^{16}C$
C) $- 1.32 \times 10^{13}C$
D) $+ 1.32 \times 10^{- 13}C$
Explanation
(c) We know that $m = 9.11 \times 10^{- 31}$ kg and $M = 75.0$kg
So, $N = \frac{M}{m} = \frac{75.0}{9.11 \times 10^{- 31}}$
$= 8.23 \times 10^{31}$ electrons
Hence, total charge on the collection is
$q = - Ne$
$= \ - (8.23 \times 10^{31})\left( 1.60 \times 10^{- 19} \right)$
$= - 1.32 \times 10^{13}$ C
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.