JEE Advanced2007PhysicsRay OpticsActual
In an experiment to determine the focal length (f) of a concave mirror by the u-v method, a student places the object pin A on the principal axis at a distance x from the pole P . The student looks at the pin and its inverted image from a distance keeping his/her eye in line with PA. When the student shifts his/her eye towards left, the image appears to the right of the object pin. Then
Options
- Ax < f
- Bf < x < 2 f
- Cx=2 f
- Dx>2 f
Correct answer
B. f < x < 2 f
Step-by-step solution
Since object and image move in opposite directions, the positioning should be as shown in the figure. Object lies between focus and centre of curvature f