Question

what is the unit of f in the equation:
f=(uv)/(u+v)

Answer 1

it has units of velocity......m/s....

Answer 2

no.......... it's unit is the unit of length.

Answer 3

it's the mirror formula in optics.

Answer 4

oh.......i thougt u and v are initial and final velocities......

Answer 5

thought*

Answer 6

I don't really know but I have given the values of u and v.
u=0.20 m
v=0.13 m
which means that both u and v probably are meters.
but I don't know what f is.
The original equation is: \[\frac{ 1 }{ f }=(\frac{ 1 }{ u })+(\frac{ 1 }{ v })\]
I found f which rounds up to 0.08 but I don't know the unit of it.

Answer 7

0.08m

Answer 8

f is focal length......so its unit is meters.......

Answer 9

its mostly calculated in cm,so you have to convert

Answer 10

oh yes I just got it now.
\[f=\frac{ (0.20 m)(0.13 m) }{ 0.20 m+0.13 m }\]
\[f=\frac{ 0.026 m^2 }{ 0.33 m }\]
\[f=\frac{ 0.026 m* m }{ 0.33 m }\]
\[f=.007878 m\]