Star A has an apparent visual magnitude of 13.4 and star B has an apparent visual magnitude of 15.4. Star A is ____ than star B.
A)2 times fainter
B)2 times brighter
C)6.3 times fainter
D)6.3 times brighter
E)29.8 times fainter

Question

Quizplus · Accepted Answer

The apparent magnitude scale is logarithmic, with a difference of 5 magnitudes corresponding to a brightness factor of 100. A difference of 2 magnitudes (15.4 - 13.4) therefore corresponds to a brightness factor of approximately 6.3, making star A 6.3 times brighter than star B.

Star a Has an Apparent Visual Magnitude of 13