In a concave mirror experiment,an object is placed at a distance ${x_1}$ from the focus and the image is formed at a distance ${x_2}$ from the focus. The focal length of the mirror would be

  • A
    ${x_1}{x_2}$
  • B
    $\sqrt {{x_1}{x_2}} $
  • C
    $\frac{{{x_1} + {x_2}}}{2}$
  • D
    $\sqrt {\frac{{{x_1}}}{{{x_2}}}} $

Explore More

Similar Questions

The separation between the screen and a concave mirror is $2r$. An isotropic point source of light is placed exactly midway between the mirror and the screen. The mirror has a radius of curvature $r$ and reflects $100\%$ of the incident light. Find the ratio of illuminances on the screen with and without the mirror.

Difficult
View Solution

The focal length of a concave mirror is $50 \ cm$. At what distance (in $cm$) should an object be placed to obtain a real and inverted image of double the size?

Difficult
View Solution

Write the relationship between the radius of curvature and the focal length for a spherical mirror.

$A$ convex mirror of focal length $f$ is placed at the origin with its reflecting surface towards the negative $x-$ axis. Choose the correct graph between $v$ and $u$ for $u < 0$.

Difficult
View Solution

Assertion : The formula connecting $u, v$ and $f$ for a spherical mirror is valid only for mirrors whose sizes are very small compared to their radii of curvature.
Reason : Laws of reflection are strictly valid for plane surfaces,but not for large spherical surfaces.

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo