Answer:
c. 277.8 nC
Step-by-step explanation:
applying,
E = kq/r²............. Equation 1
Where E = electric field intensity, q = charge, r = distance, k = coulomb's constant.
make q the subject of the equation
q = Er²/k............... Equation 2
From the question,
Given: E = 10000 N/C, r = 0.5 m
Constant: k = 9×10⁹ Nm²/C²
Substitute these values into equation 2
q = (10000×0.5²)/(9×10⁹)
q = 277.8×10⁹
q = 277.8 nC
Hence the right option is c. 277.8 nC