Question

A candle flame 1.6cm high is imaged in a ball bearing of diameter 04cm. If the ball bearing is 20cm away from the flame, find the location and the height of the image.

Answer 1

i think the answer is right

Answer 2

Given :

i think in question diameter of ball bearing should be 0.4cm

hi= 1.6cm

diameter =d= 0.4 cm

r= 0.2cm

u= 20cm

1/v +1/u= /1f

- 1/20 +/1v= 2/ 0.2

1/v= 1/20 +10

= 1+200/20

v= 20/201 = 0.1cm= 1mm inside ball bearings

m= hi/ho =  - v/ u = - 0.1/ - 20 = 1/200

hi/ho= 1/200

hi= hox 1/200

=1.6 /200

= 16/2000

=0.008cm

∴ hi= 0.008cm