Electron microscope was invented by
1). Knoll and Ruska
2). Robert Koch
3). Leeuwenhoek
4). C.P. Swanson
1. If objects appear enlarged and inverted in a rear view mirror, then which type of mirror is used?
2. The sky appears blue because of
3. The bending of light when it passes around a corner or a slit is due to ________
4. ?Which one of the following phenomena is used in optical fibres?
5. The type of mirrors used in the headlamp of cars is
6. Earth is the _______ planet from the Sun.
8. ?If the earth were to spin faster, acceleration due to gravity at the poles: