Saved Bookmarks
| 1. |
Light incident normally on a plane mirror attached to a galvanometer coil retraces backwards as shown in Fig. 9.33. A current in the coil produces a deflection of 3.5^(@) of the mirror. What is the displacement of the reflected spot of light on a screen placed 1.5 m away? |
| Answer» SOLUTION :The reflected rays get deflected by TWICE the angle of ROTATION of the mirror. Therefore, `d//1.5 = TAN 7^(@)`. Hence `d = 18.4 cm.` | |