Answer:
Epx= - 21.4N/C
Epy= 19.84N/C
Step-by-step explanation:
Electric field theory
The electric field at a point P due to a point charge is calculated as follows:
E= k*q/r²
E= Electric field in N/C
q = charge in Newtons (N)
k= electric constant in N*m²/C²
r= distance from load q to point P in meters (m)
Equivalences
1nC= 10⁻⁹C
known data
q₁=-2.9nC=-2.9 *10⁻⁹C
q₂=5nC=5 *10⁻⁹C
r₁=0.840m
![r_(2) =\sqrt{1^(2) +0.8^(2) } =√(1.64)](https://img.qammunity.org/2020/formulas/physics/college/sceyad1sz2p5ruk019eft52lcoofi76dbr.png)
![sin\beta =(0.8)/(√(1.64) ) =0.6246](https://img.qammunity.org/2020/formulas/physics/college/bxmi2fguqj10kywcsi2vfpsvws2yjew14k.png)
![cos\beta =(1)/(√(1.64) ) =0.7808](https://img.qammunity.org/2020/formulas/physics/college/tmer2y81gtilvu3fmiwef8thremx5x64eu.png)
Calculation of the electric field at point P due to q1
Ep₁x=0
![Ep_(1y) =(k*q_(1) )/(r_(1)^(2) ) =(8.99*10^(9)*2.9*10^(-9) )/(0.84^(2) ) =36.95(N)/(C)](https://img.qammunity.org/2020/formulas/physics/college/gma3vdgaksbo8xso9fe9glhho0qzibnvw9.png)
Calculation of the electric field at point P due to q2
![Ep_(2x) =-(k*q_(2) *cos\beta )/(r_(2)^(2) ) =-(8.99*10^(9)*5*10^(-9) *0.7808 )/((√(1.64))^(2) ) =-21.4(N)/(C)](https://img.qammunity.org/2020/formulas/physics/college/f3jgrdoytgpdiijvfowbg6rhkgomvtm2a3.png)
![Ep_(2y) =-(k*q_(2) *sin\beta )/(r_(2)^(2) ) =-(8.99*10^(9)*5*10^(-9) *0.6242 )/((√(1.64))^(2) ) =-17.11(N)/(C)](https://img.qammunity.org/2020/formulas/physics/college/10jqhc2hjnsl26zg8u90oio9mx79uvcc8s.png)
Calculation of the electric field at point P(0,0) due to q1 and q2
Epx= Ep₁x+ Ep₂x==0 - 21.4N/C =- 21.4N/C
Epy= Ep₁y+ Ep₂y=36.95 N/C-17.11N =19.84N/C