Two opposite and equal charges of magnitude coulomb each when placed cm apart form a…
PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
Two opposite and equal charges of magnitude 4×10−8 coulomb each when placed 2×10−2 cm apart form a dipole. If this dipole is placed in an external electric field of 4×108 N/C, the value of maximum torque and the work required in rotating it through 180∘ from its initial orientation which is along electric field will be: (Assume rotation of dipole about an axis passing through centre of the dipole):
(a) 64×10−4 N-m and 44×10−4 J
(b) 32×10−4 N-m and 32×10−4 J
(c) 64×10−4 N-m and 32×10−4 J
(d) 32×10−4 N-m and 64×10−4 J