If the focal length of the objective lens is increased then the magnifying power of:
1. | microscope will increase but that of the telescope decrease. |
2. | microscope and telescope both will increase. |
3. | microscope and telescope both will decrease. |
4. | microscope will decrease but that of the telescope will increase. |
A microscope is focused on a mark on a piece of paper and then a slab of glass of thickness 3 cm and a refractive index 1.5 is placed over the mark. How should the microscope be moved to get the mark in focus again?
1. 1 cm upward
2. 4.5 cm downward
3. 1 cm downward
4. 2 cm upward