The focal length of a concave mirror is 30 , | vedclass

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

Question

(A) $(i)$ If the image is real and inverted:$m = -v/u = -3$,which implies $v = 3u$. Given $f = -30 \, cm$.Using the mirror formula $\frac{1}{v} + \fra

Vedclass · Accepted Answer

$40 \, cm$ and $20 \, cm$

Vedclass · Answer

(A) $(i)$ If the image is real and inverted:$m = -v/u = -3$,which implies $v = 3u$. Given $f = -30 \, cm$.Using the mirror formula $\frac{1}{v} + \frac{1}{u} = \frac{1}{f}$:$\frac{1}{3u} + \frac{1}{u} = \frac{1}{-30} \Rightarrow \frac{1+3}{3u} = \frac{1}{-30} \Rightarrow \frac{4}{3u} = \frac{1}{-30} \Rightarrow u = -40 \, cm$.Thus,the object is placed at $40 \, cm$ in front of the mirror.$(ii)$ If the image is virtual and erect:$m = -v/u = +3$,which implies $v = -3u$. Given $f = -30 \, cm$.Using the mirror formula $\frac{1}{v} + \frac{1}{u} = \frac{1}{f}$:$\frac{1}{-3u} + \frac{1}{u} = \frac{1}{-30} \Rightarrow \frac{-1+3}{3u} = \frac{1}{-30} \Rightarrow \frac{2}{3u} = \frac{1}{-30} \Rightarrow u = -20 \, cm$.Thus,the object is placed at $20 \, cm$ in front of the mirror.

The focal length of a concave mirror is $30 \, cm$. Find the position of the object in front of the mirror so that the image is three times the size of the object.

Similar Questions

$A$ beam of light is incident through the holes on side $A$ and emerges out of the holes on the other face of the box as shown in the Figure. Which of the following could be inside the box?

Which of the following statements is true regarding a real image of an object?

Discuss the position and nature of the image formed by a concave mirror when the object is moved from infinity towards the pole of the mirror.

What are the advantages and disadvantages of using a convex mirror for seeing traffic at the rear?

Vedclass Test Series

Exam Paper Generator

Online Exam Module