Question

Q6: On object is 20 cm in front of convex mirror. If the image height is 1/5 times the object height, determine the image distance

Answer 1

Answer:

here is the ans

Explanation:

The calorific value of kerosene is 45,000 kJ/kg. What is the mass of kerosene to be taken

to produce an energy of 27,00,000 kJ

Answer 2

Given :

In convex mirror,

Object distance : 20 cm

Magnification : 1/5

To find :

The image distance

Solution :

We know that,

» The linear magnification produced by a mirror is equal to the ratio of the image distance to the object distance with a minus sign and it is equal to the ratio of image height and object height. that is,

$\boxed{\bf m = \dfrac{h'}{h} = - \dfrac{v}{u}}$

where,

• h' denotes height of image
• h denotes object height
• v denotes image distance
• u denotes object distance

By substituting all the given values in the formula,

$\dashrightarrow\sf m = - \dfrac{v}{u}$

$\dashrightarrow\sf \dfrac{1}{5} = - \dfrac{v}{ - 20}$

$\dashrightarrow\sf v = \dfrac{20}{5}$

$\dashrightarrow\sf v = 4 \: cm$

Thus, the image distance is 4 cm.