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Grade 9General Physics

An object is placed 20cm from a convex mirror its image is formed 12cm from mirror, find the focal length of the mirror

Profile image of Šùdhïr Pråšãd sâhù
5 Years agoGrade 9
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2 Answers

Profile image of Pooman Arora
5 Years ago
1/v + 1/u = 1/f
1/12 - 1/20 = 1/f
5-3/60 =1/f
2/60 = 1/f 
1/30 = 1/f 
f= 30
This was done by mirror formula 
Hope you understood
 
Profile image of CHAITANYA PARATE
4 Years ago
Answer is 30.
By using mirror formula 1/f=1/u+1/v.
1/f= 5-3/60
1/f = 30.
So this is the short answer.
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