Question

Q.10 (a) An object of height 10cm. is placed at a distance of 40cm. infront of a concave mirror of focal length 20.0cm. Find the length of image. [2] When the weight of a body is greater than the buoyant force in a liquid,

(i) What will happen to the body in the fluid. [2]
(ii) What is the apparent weight of the body. [2]
(c)
(1) What are the advantage of wind energy. [2]
(ii) What are the traditional uses of wind energy. [2]​

Answer 1

(a) An object of height 10cm. is placed at a distance of 40cm. infront of a concave mirror of focal length 20.0cm. Find the length of image

→Don't bother about the object height.As per sign convention

Object distance u=-10 cm

Focal length of concave mirror f=-20 cm

Using mirror formula

(1/v)+(1/u)=(1/f)=>v=uf/u-f

So v=(-10)×(-20)/(-10-(-20))=200/10=20 cm.

Distance of the image is 20 cm.

Image will be formed behind the mirror and image will be virtual and erect.

Answer 2

Answer:

An object of Height

Explanation: