Question

Please help me with this question

Answer 1

Answer:

u=-10

v=40

let focal length be f.

1/f=1/v-1/u

1/f=1/40-(-1/10)

1/f=1/40+1/10

1/f=(1+4)/40

1/f=5/40

1/f=1/8

f=8 cm

Explanation:

Answer 2

Explanation:

if f = ?

u = - 10

v = -40 cm

mirror formula is

1/f =1/v + 1/u

1/f =- 1/40- 1/10

f = -40/5

f= -8