Question

2. It object is placed at 20cm for on Concave
mimor of focal length 10cm. find position,
Size & Nature of Image​

Answer 1

Explanation:

Given:

 Focal length of concave mirror, f = -20 cm

Distance of object from the mirror, u = -10 cm

use formula, 1/v + 1/u = 1/f 

or, 1/v = 1/f - 1/u 

or, 1/v = 1/-20 - 1/-10 

or, 1/v = -1/20 + 1/10 = 1/20 

or, v = +20cm 

hence, image position is the 20cm right side from the pole of the concave mirror as shown in the diagram. The image is straight and bigger than the object.

Answer 2

Answer:

Given:

Focal length of concave mirror, f = -20 cm

Distance of object from the mirror, u = -10 cm

use formula, 1/v + 1/u = 1/f

or, 1/v = 1/f - 1/u

or, 1/v = 1/-20 - 1/-10

or, 1/v = -1/20 + 1/10 = 1/20

or, v = +20cm

hence, image position is the 20cm right side from the pole of the concave mirror as shown in the diagram. The image is straight and bigger than the object.

solution