11th Class Physics MCQS
A double convex lens acts as diverging lens when the object is
Inside the focus
A a large distance from lens
At infinity
A way from focus
Image formed by a concave lens is
Erect
Virtual
None of these
Real
The accepted value for speed of light in vacuum
2.99 x 108m – sec-1
2.99 x 108km – sec-1
2.99 x 108m – h-1
2.99 x 106m – sec-1
The magnifying power is also called
Strength of eye
Resolving power
None of these
Angular magnification
The optical fibre is covered for protection by
Steel jacket
Diamond jacket
Glass jacket
Plastic jacket
A convex lens can be used as
Spectrometer
Telescope
Simple microscope
Compound microscope
The device used to study the spectra from different sources of light is
Spectrometer
Microscope
Telescope
Optical fibre
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