b) An electric dipole in a uniform electric field of magnitude 5.0×105 N/C that is directed parallel to the plane of the figure. The charges are
±1.6×10-19 C; both lie in the plane and are separated by 0.125 nm =
0.125 ×10-9 m. Find (i) the magnitude and direction of the electric dipole moment; (ii) the magnitude and direction of the torque.
Answers
The Charges Are Plusminus 1.6 X 10-19 C; Both Lie In The Plane And Are Separated ... Find The Net Force Exerted By The Field On The Dipole; The Magnitude And ... field with magnitude 5.0 x 105 N/C directed parallel to the plane of the figure. ... Figure 1.0 (a) an electric dipole (b) Direction of the electric dipole moment, ...
Given:
|E| = 5.0×10^5 N/C
q1 = +1.6×10^-19 C
q2 = -1.6×10^-19 C
|q| = 1.6×10^-19 C
d = 0.125×10^-9 m
To Find :
i) The magnitude and the direction of the electric dipole moment(P).
ii) The magnitude and the direction of the torque(T).
Solution:
i) For the magnitude of electric dipole moment, we know
|P| = |q| × |d|
= 1.6×10^-19 × 0.125×10^-9
= 2×10^-27 Cm
The direction of the dipole moment is always from negative to positive charge.
ii) For the magnitude of the torque
|T| = |P| × |E| Sinθ , ( θ = 90 , The dipole is parallel to plane of figure)
= 2 × 10^-27 × 5 × 10^5
= 1 × 10^-21 NC^2/m
The direction of the torque is clockwise.
Hence, the magnitude of the dipole moment is 2×10^-27 Cm
Hence, the magnitude of Torque is 1 × 10^-21 NC^2/m
#SPJ2