- (A) radiate electromagnetic energy with a continuous distribution of wavelength
- (B) absorb particular wavelengths when white light is incident on them
- (C) radiate electromagnetic energy of discrete characteristic wavelength
- (D) emit either invisible or visible light
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- (A) photo electric effect
- (B) ionization
- (C) shadow photograph
- (D) any of above
- (A) 1st to 5th orbit
- (B) 2nd to 5th orbit
- (C) 3rd to 5th orbit
- (D) 4th to 5th orbit
- (A) band spectrum
- (B) line spectrum
- (C) continuous spectrum
- (D) absorption spectrum
- (A) three
- (B) four
- (C) five
- (D) six
- (A) The illumination of the target metal by ultra-violet radiation
- (B) The bombardment of the target by protons
- (C) The bombardment of target by electrons
- (D) The absorption of radiation by the target metal
- (A) Reducing the pressure or cooling the target
- (B) Increasing the temperature of the filament.
- (C) Using a target element of higher atomic number
- (D) Increasing the potential difference between the cathode and the target
- (A) B-rays
- (B) X-rays
- (C) Far infrared
- (D) Infrared
- (A) he/ev
- (B) he/Vc
- (C) eV/h
- (D) impossible to predict
- (A) A & B
- (B) B & C
- (C) A & C
- (D) A B & C
