Physics Circle home Student Login

Home›Chapters›Ray Optics PYQs›Reflection & Mirrors›Question 41

JEE Main 2019 (9 Apr, Shift 1) · Reflection & Mirrors

Reflection & Mirrors question from JEE Main 2019 (9 Apr, Shift 1)

Q41JEE Main 2019 · 9 APR · SHIFT 1Medium

Reflection & Mirrors

A concave mirror for face viewing has focal length of 0.4 m. The distance at which you hold the mirror from your face in order to see your image upright with a magnification of 5 is:

Show answer and solution

Answer: (b)

  1. Concave mirror: f=−0.4 mf = -0.4\text{ m}; upright image, m=+5m = +5.
  2. m=ff−u⇒5=−0.4−0.4−um = \frac{f}{f - u} \Rightarrow 5 = \frac{-0.4}{-0.4 - u}
  3. −2−5u=−0.4⇒u=−0.32 m-2 - 5u = -0.4 \Rightarrow u = -0.32\text{ m}
  4. So the answer is (b) 0.32 m.
Report a mistake

More questions on Reflection & Mirrors