1.

Light incident normally on a plane mirror attached to a galvenometer coil reflects backward as shown in figure. A current in the coil produes a deflection of 3.5^(@) if the mirror. The displacement of the reflected spot of light on ascreen placed 1.0 m away is

Answer»

`27.5 m`
`48.9 CM`
`24.5 cm`
`12.2 m`

SOLUTION :Angle of deflection is `theta = 3.5^(@)`, Distance between the screen and the MIRROR is `= 2.0 m`
The reflected rays gets deflected by an amount TWICE the angle of deflection , i.e., `2theta = 7.0^(@):. tan 2 theta = d/2`
`rArr d = 2 XX tan 7^(@)= 2 xx 0.1227 = 0.245 m = 24.5 cm`


Discussion

No Comment Found

Related InterviewSolutions