An object is placed near a concave mirror having a radius of curvature of magnitude 60 cm. how far should you place the object from the mirror so that the lateral magnification produced by the mirror will be 2.5?

u = 18 cm

Explanation:

given,

radius of curvature = 60 cm

magnification of mirror = 2.5

distance of object  = ?

R = 2 f

f = R/2

f = 60/2 = 30 cm

v = -2.5 u

now,

Using mirror formula

u = 0.6 x 30

u = 18 cm

distance of object be equal to u = 18 cm

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures

k2s for potassium sulphide