science physics
posted by Todd .
1.) What is the Magnitude of the electrostatic force on a +5 C charge 1.75 m to the left of a 2.5 C charge? (show your work)
2.) In What direction does the force on the +5 C charge act?
3.)Calculate the magnitude of the electric field of the 2.5 C charge at the location of the +5 c Charge.
4.) Calculate the magnitude of the total electric field at a point 2m above the +5 C charge. (superposition)
5.) Calculate the magnitude of the electrostatic potential at this point.

1,2). k =9•10⁹ N•m²/C²,
q₁=5 C, q₂=  2.5 C.
F=k•q₁•q₂)/r² =
=9•10⁹•5•2.5/1.75² =3.67•10¹⁰ N (to the right).
3). E=kq₂/r² =9•10⁹•2.5/1.75²=
=7.35•10⁹ V/m(to the right).
4). E₁=k q₁/a² = 9•10⁹•5/2²=
=1.125•10¹⁰ V/m,
b=sqrt{2²+1.75²}=2.66 m,
E₂= kq₂/b² =
=9•10⁹•2.5/2.66²=3.18•10⁹ V/m.
cosα=2/2.66=0.75,
E=sqrt{E₁²+E₂²2E₁E₂cosα} =
=sqrt{(1.125•10¹⁰)² +(3.18•10⁹)² 
2•1.125•10¹⁰•3.18•10⁹•0.75} =
=9.13•10⁹ V/m.
5). φ=φ₁+φ₂ =k q₁/a + k q₂/b =
= k (q₁/a + q₂/b) =
= 9•10⁹(5/2  2.5/2.66) =1.4•10¹⁰ V.