Q. A dim star of magnitude + 14.5 explodes into a nova a magnitude +2. The factor by which the brightness of the star has increased is
A) 12.5
B) $10^{2}$
C) $10^{3}$
D) $10^{5}$
Explanation
(d) $\frac{I_{1}}{I_{2}} = (100)^{\left( m_{1} - m_{2} \right)/5} = (100)^{(14.5 - 2)/5} = (100)^{5/2} = 10^{5}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.