(c) Efficiency, $\eta = 1 - \frac{T_{2}}{T_{1}} = 1 - \frac{500}{800}$ $\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ = \frac{3}{8} = 0.375$
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.