an object I placed in front of the of focal length 20 cm what is the nature of image formed of the object distance is 50 cm.

Focal length f=−20 cm

Object distance u=−50 cm

Using

v

1

−

u

1

=

f

1

Or

v

1

−

(−50)

1

=

−20

1

We get v=−14.3 cm

Since, v is negative. So image formed is virtual.

Hence, virtual image is formed at a distance of 14.3 cm in front of the lens.

Explanation and Examples

let the mass of the compressor be

mass (m):

height in x axis is (h1)

height in y axis be (h2):

Height difference: h2-h1

displacement x force:

mass x gravity x height

(m)*9.8*(height difference) = ___ J

Since gravity is forcing down, it would be negative!

Put the values that you require and get the answer.