Question

Point charges q1=− 4.90 nC and q2=+ 4.90 nC are separated by distance 3.90 mm , forming an electric dipole.

Part A

Find the magnitude of the electric dipole moment.

Express your answer in coulomb meters to three significant figures.

Part B

What is the direction of the electric dipole moment?

Part C

The charges are in a uniform electric field whose direction makes an angle 36.7 ∘ with the line connecting the charges. What is the magnitude of this field if the torque exerted on the dipole has magnitude 8.00×10⁻⁹ N⋅m ?

Express your answer in newtons per coulomb to three significant figures.

Answer 1

Point charges q1=- 4.90nC and q2=+ 4.90nC are separated by a distance of 3.90mm , forming an electric dipole.

A.)

The magnitude of the electric dipole moment= p =(4.90*10^-9)( 3.90*10^-3 ) =1.911*10^-11 Cm

B.)

The direction of the electric dipole moment is from q1 to q2

C.)

The charges are in a uniform electric field E whose direction makes an angle of 36.7degrees with the line

connecting the charges.

The torque exerted on the dipole = t =8.00*10^−9 N.m

pEsinO = torque = t

E = t / psinO

E = 8.00*10^−9/1.911*10^-11*(sin36.7)

E = 8.00*10^−9/1.911*10^-11 (0.5976)

E = 700.51 N/C = 7.0*10^2 N/C

the magnitude of this field is E = 7.00*10^2 N/C