i asked if v and u are unknown then how will u find them the focal length is - Science - Light - Reflection and Refraction

Question

i asked if v and u are unknown then how will u find them ? the
focal length is given and m is also given then how will u find u
and v plzzz don t say the mirror or lens formula or m=v/u or 0v/u i
need the formula for both lens and mirror the formula that be like
m=f/f-u like that i need for lens and mirror and also finding v
like m=f-v/f i don t know the correct formula plzzz tell me the
correct ans

Pintu B. · Accepted Answer

Dear Student ,

We know that ,m=vu⇒v=muNow applying the above equation in len's makers formual we can write that ,1v-1u=1f⇒1mu-1u=1f⇒1m=uf+1⇒m=fu+fSo ,v=mu=ufu+fNow applying the above equation in mirror formual we can write that ,1v+1u=1f⇒1mu+1u=1f⇒1m=uf-1⇒m=fu-fTherefore , v=mu=ufu-f
Hope this helps you
Regards