The least distance of distinct vision for a normal eye is:
A. 15 cm
B. 25 cm
C. 30 cm
D. 40 cm
Magnifying power of simple microscope:
A. increase with increase in focal length
B. increase with decrease in focal length
C. no effect with decrease or increase with focal length
D. list distance of distinct vision
If an object is placed away from 2f of a converging lens then the image will be:
A. real and erect
B. virtual and erect
C. real and inverted
D. virtual
The power of a concave lens is:
A. real
B. virtual
C. positive
D. negative
Unit of power of a lens is:
A. meter
B. watt
C. diopter
D. horsepower
The diameter of a lens is called:
A. focal length
B. principal axis
C. aperture
D. radius of curvature
Electron moves in the orbit as:
A. Simple vibratory motion
B. Standing wave motion
C. Vibratory motion like up and down
D. S.H.M likes the sound
Compton effect proves the:
A. Photon theory of light
B. Dual nature of light
C. Wave nature of light
D. Uncertain nature of light
For confinement of electron in a box of radius 10-14m the electron, speed should be:
A. 107m/sec
B. Should be greater than the speed of light.
C. Be zero
D. Not be wave-like
A three-dimensional image is obtained by:
A. Electron microscope
B. Scanning electron microscope
C. Magnetic imaging
D. None of the above
