An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image,

Hint—Draw ray diagrams indicating the direction of incident ray and reflected ray.

Radius of curvature of convex mirror, R = 30 cm. Focal length of convex mirror, f=R/2=30cm/2=15cm Now h=5cm,u=-20cm,v=?,h'=? Using the mirror formula 1/f=1/u+1/v, we have 1/v=1/f=1/u=1/15=1/-20=1/15+1/20=(4+3)/60 v=60/7=8.6cm. Thus, image is formed at a distance of 8.6cm...

(c) both concave mirror and convex lens.

(iii) 6 m Explanation: As David moves 1 m towards the mirror, the image also moves 1 m towards the mirror. Now the distance between David and mirror is 3 m and...

Given, u=-10 cm, f=+15 cm,v=? From mirror formula, 1/f=1/v+1/u or 1/v=1/f=1/u =1/v=1/15=1/(-10)=1/15+1/10=(2+3)/30 or  v=30/5=+6 cm That is image is formed at a distance of 6 cm from the mirror behind it. The image is erect and virtual.

(d) 15 cm behind the mirror. EXPLANATION:  The option can be selected by suitable reasoning. In a convex mirror, the object at infinity has its image at the focus behind the mirror....

Case 1: When image is real v/u=-2x/x=-2 v= -2u 1/v+1/u=1/f=1/20 => 1/u-1/2u=1/20 =>1/2u=1/20 =>u=10 cm

(a) Virtual image formed is larger in size in case of concave mirror.

(a) Real, inverted and same in size because object is at the centre of curvature of the mirror.

(d) Focal length of the spherical mirror does not depend on the medium in which it placed.