Distance between object and its image (magnified by -1/3) is 30 cm. The focal length of the mirror used is (x/4) cm, where magnitude of value of x is _ _ _

Optics: JEE Main 2025 Physics question

JEE Main 2025 · 4 Apr, Morning shift · Q50

JEE Main 20254 Apr, Morning shiftPhysicsMediumOptics190× since 2002

Distance between object and its image (magnified by

-\frac{1}{3}

) is 30 cm. The focal length of the mirror used is

\left(\frac{x}{4}\right)

cm, where magnitude of value of

x

is ______

Your answerType your answer. Integers and decimals are accepted.