Fields & Potential Homework Solutions

[ChloeFoulkes]

Homework Statement

The electric field on the x-axis due to a point charge fixed at the origin is given by E=(a/x2)i, where a = 6.00 kVm and x is not equal to zero.
a) Find the magnitude and sign of the point charge
b) Find the potential difference between the points on the x-axis at x=1 m and x=2 m.
c) What is the potential energy of a proton at both positions?

Homework Equations

E=kq/^2
Vb-Va=-∫Edl

The Attempt at a Solution

a) I've got the magnitude but I am unsure how to find the charge?
b) using Vb-Va=-∫Edl, but if I am honest, I am not 100% sure how to use the equation
c) haven't attempted yet

 

[Tanya Sharma]

Homework Statement

The electric field on the x-axis due to a point charge fixed at the origin is given by E=(a/x2)i, where a = 6.00 kVm and x is not equal to zero.
a) Find the magnitude and sign of the point charge
b) Find the potential difference between the points on the x-axis at x=1 m and x=2 m.
c) What is the potential energy of a proton at both positions?

Homework Equations

E=kq/^2
Vb-Va=-∫Edl

The Attempt at a Solution

a) I've got the magnitude but I am unsure how to find the charge?
b) using Vb-Va=-∫Edl, but if I am honest, I am not 100% sure how to use the equation
c) haven't attempted yet

What is the magnitude of charge you have calculated ?

For finding the sign of charge ,does the Electric field points towards or away from the point charge placed at the origin ?

 

[ChloeFoulkes]

for a) i equalled a/x^2 and kq/x^2 cancelling to give q=a/k. subbing in values i got 6.67x10^-7 C. How would i know which direction the field is pointing?