A tube of length 30 cm has its inner lateral surface

Last updated: 6/13/2023

A tube of length 30 cm has its inner lateral surface blackened Two lenses of focal lengths 10 cm and 20 cm are fixed at the ends of the tube For same beam intensities of spots on screen are I and 1 for arrangement 1 and arrangement 2 If the ratio of I I is of the form N find N I2 Beam 10 cm Tube 20 cm Screen Arrangement 1 Beam 20 cm Tube 10 cm Screen Arrangement 2