Q.
Figure (i) shows a conducting loop being pulled out of a magnetic field with a speed $v$. Which of the four plots shown in figure (ii) may represent the power delivered by the pulling agent as a function of the speed $v$
A) $a$
B) $b$
C) $c$
D) $c'$
Explanation
(b) $P = Fv = Bil \times v = B\ \left( \frac{Bvl}{R} \right)l \times v = \frac{B^{2}v^{2}l^{2}}{R} \Rightarrow P \propto v^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.