Consider two electric dipoles, each consisting of two equal and opposite point c
ID: 2226489 • Letter: C
Question
Consider two electric dipoles, each consisting of two equal and opposite point charges at the ends of an insulating rod of length d. The dipoles sit along the x-axis a distance r apart, oriented as shown below. Their finite separation r >> d > 0 (far enough apart that they may be treated as point dipoles but not so far that they don't interact) At the instant pictured, the dipole ON THE LEFT will feel: a force to the left and a torque trying to make it rotate clockwise. a force to the left and a torque trying to make it rotate counterclockwise. a force to the left and no torque. a force to the right and a torque trying to make it rotate clockwise. a force to the right and a torque trying to make it rotate counterclockwise. a force to the right and no torque. no force and a torque trying to make it rotate clockwise. no force and a torque trying to make it rotate counterclockwise. no force and no torque.Explanation / Answer
Under the influence of the -ve charge of the horizontal dipole the force acting will be on the right(attractive force as +ve side of the dipole on the left is closer). Also due to that the force generated on the positive side of the left dipole (qE) will generate a counter force on the negative end of -qE hence giving it a torque in the clockwise direction. There will be some influence of the electric field of the right dipole as the distance is sufficiently small so as to make them interact (as mentioned in the question) Hope this helps!