Question

a concave mirror used òn a automoblue has 3m radius of curvsture. if a bus is located at 5m from this miror . find position , nature , and size .

Answer 1

Given

R = +3 m , f = +1.5m

Object Distance u = -5m

Image Distance v = ?

Image size h' = ?

Using mirror formula = $\huge\frac{1}{f}$ = $\huge\frac{1}{u}$+$\huge\frac{1}{v}$

• $\huge \frac{1}{v }$ = $\huge \frac{1}{f}$ - $\huge\frac{1 }{ u }$

+$\huge \frac{1 }{1.5 }$ - $\huge \frac{1 }{-5 }$ = $\huge \frac{5+1.5}{7.5}$

v = $\huge \frac{7.5}{6.5}$

= 1.15m

• The image is 1.15 m behind the mirror.

Magnification, m = $\huge\frac{h'}{h }$ = - $\huge\frac{1.15 }{- 5 }$ = + 0.23

• The image is vitual , upright and smaller in size than the object by a factor of 0.23 ( about one - fourth.)

Hope it helps you