1. ELECTRIC FIELD INTENSITY
By:
Engr. Hinesh Kumar
Lecturer
I.B.T, LUMHS

2. Electric Field Intensity
The strength of the electric field is measured using a quantity called the electric field intensity. The greater the electrical field intensity the stronger the field.
Electric intensity is defined as the force experienced per unit positive charge at a point placed in the electric field.

3. Cont…
The electric field is directed from positive charge and toward the negative charge.
The S.I unit of electric filed intensity is Newton/Coulomb (N/C).

4. Electric Field Intensity near an Isolated Point Charge q
Imagine a very small positive charge q˳ placed at a distance r from point charge q˳
The magnitude of force on q˳ due to the charge q is q q˳ r

5. Cont… The final formula of electric field intensity is:
The direction of the intensity of electric field is that the electric force

6. Example # 1
Charges each of +3 μC are placed at three corners of a square whose diagonal is 6 cm long. Find the field intensity at the point of inter section of diagonals.
Solution:
The field at O due to charges at A and C mutually cancel each other being equal and opposite.
Then the net field is A D O B C

7. Example# 2
Find the electric intensity midway between the charges 1.67*10-7 coulomb and 1.67*10-7 separated by the distance of 60 cm.
Solution q˳ q2 q1
30 cm
30 cm

8. Cont…
Since q1=q2 and r1=r2, than formula becomes