COMEDK · Physics · 16. Waves and Sound
A star A is 100 times brighter than star \(B\). Then, \(m_{B}-m_{A}\) the difference in their apparent magnitudes is
- A 100
- B \(0.01\)
- C 5
- D \(0.2\)
Answer & Solution
Correct Answer
(C) 5
Step-by-step Solution
Detailed explanation
Given, \(\frac{I_{A}}{I_{B}}=100\) Using magnitude equation, \[ \begin{aligned} m_{B}-m_{A} &=-2.5 \log \left(\frac{I_{B}}{I_{A}}\right) \\ &=-2.5 \log \left(\frac{1}{100}\right)=-2.5 \times-2=5 \end{aligned} \]
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