An object that is 2 cm tall is 18 cm in front of a converging lens and creates a real image 8 cm beyond the lens. what is the focal length of the lens?
what is the height of the image?

The focal length of the lens is 5.54 cm and the height of the image is -0.89 cm.

Explanation:

Given that,

Height of object h = 2 cm

Object distance u= -18 cm

Image distance v= 8 cm

We need to calculate the focal length of the lens

Using formula of lens

Where, f = focal length

Put the value into the formula

(II). We need to calculate the height of the image

Using formula of magnification

Put the value into the formula

Hence, The focal length of the lens is 5.54 cm and the height of the image is -0.89 cm.

absorption lines are where light has been absorbed by the atom thus you see a dip in the spectrum whereas.

emission spectra have spikes in the spectra due to atoms releasing photons at those wavelengths.

explanation:

a and b sometimes have a positive value