Question

7. Write u,v,r,f values if the object is placed at 20 CM in front of concave mirror.whose focal length
is 10 centimetre.
​

Answer 1

Answer:

Focal length = 20 cm

radius of curvature = 2 [ focal length ]

                                = 2 [ 20 cm ]

                                = 40 cm

object distance = 20 cm ( v )

focal length = object distance + image distance

using the formula : 1/f  = 1/v + 1/u

1/f = 1/v + 1/u

1/10 cm = 1/20 cm + 1/u

1/u = 1/10 cm - 1/20 cm

1/u = 1/-10 cm

∴ v = 20 cm

  u = -10 cm

  r = 40 cm

  f = 20 cm

F.o.l.l.o.w  me if the answer was helpful