The electric field intensity generated by a single point charge is given by
![E(r)=k(q)/(r^2)](https://img.qammunity.org/2019/formulas/physics/high-school/37cdknijmt6wk24ltdid1abkueet9jktq8.png)
where
k is the Coulomb's constant
q is the charge
r is the distance from the charge
In this problem, the charge is
and we are asked to calculate the field at distance
, so the electric field is
![E(9.0 m)=(8.99 \cdot 10^9 Nm^2C^(-2))(25 \cdot 10^(-6) C)/((9 m)^2)=2775 V/m](https://img.qammunity.org/2019/formulas/physics/high-school/kqzlc6sonmgqyby864vng8uw4ophzccexj.png)