In an experiment for the determination of foc | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) In the absence of the convex mirror,the real and inverted image of the object is formed at a distance $v$ from the convex lens. Using the lens for

Vedclass · Accepted Answer

$25$

Vedclass · Answer

(C) In the absence of the convex mirror,the real and inverted image of the object is formed at a distance $v$ from the convex lens. Using the lens formula $\frac{1}{f} = \frac{1}{v} - \frac{1}{u}$:$\frac{1}{v} = \frac{1}{f} + \frac{1}{u} = \frac{1}{20} + \frac{1}{-30} = \frac{3-2}{60} = \frac{1}{60}$$v = 60 \ cm$.When a convex mirror is introduced between the lens and the image position such that the final image is formed at the object $O$ itself,the light rays must strike the mirror normally. This implies that the rays are directed towards the centre of curvature of the mirror.The distance of the centre of curvature from the mirror is $R = v - d$,where $d$ is the distance between the lens and the mirror.$R = 60 \ cm - 10 \ cm = 50 \ cm$.The focal length of the mirror is $f_m = \frac{R}{2} = \frac{50 \ cm}{2} = 25 \ cm$.

Similar Questions

When sunlight falls normally on Earth,a luminous flux density (illuminance) of $1.57 \times 10^5 \; lm/m^2$ is produced on Earth. The distance of Earth from the Sun is $1.5 \times 10^8 \; km$. The luminous intensity of the Sun in candela is:

In the diagram shown,all the velocities are given with respect to the earth. What is the relative velocity of the image in mirror $(1)$ with respect to the image in mirror $(2)$? The mirror $(1)$ forms an angle $\beta$ with the vertical.

$A$ $60 \text{ W}$ bulb is hung over the center of a table of size $4 \text{ m} \times 4 \text{ m}$ at a height of $3 \text{ m}$. The ratio of the intensities of illumination at a point on the center of the edge $(A)$ and at the corner of the table $(B)$ is:

$A$ camera lens is set at $f/2$ with an exposure time of $1/100 \ s$. If the lens is set at $f/4$,what will be the correct exposure time?

Vedclass Test Series

Exam Paper Generator

Online Exam Module