ATOM -2

The energy of photons is directly proportional to:

• Wavelength

• Frequency

• Intensity

• Amplitude

The unit of Planck's constant is:

• Joule-second

• Joule

• Electron-volt

• Newton-second

For photoelectric emission to occur, the energy of incident light must:

• Equal the work function of the metal

• Be less than the work function of the metal

• Be greater than the work function of the metal

• Depend only on intensity

The radius of the first Bohr orbit is approximately:

• 5.29 nm

• 5.29 x 10-10 m

• 1 nm

• 1 ×10-10 m

In a p-n junction diode under reverse bias:

• Current flows freely

• Current is very small

• Current is high due to electrons

• None of these

Which of the following explains the wave nature of particles?

• Photoelectric effect

• de Broglie hypothesis

• Compton effect

• Rutherford scattering

The work function of a metal is 2.0 eV. The threshold wavelength is:

• 620 nm

• 310 nm

• 400 nm

• 6200 nm

The Balmer series of hydrogen spectrum lies in:

• Visible region

• Infrared region

• Ultraviolet region

• X-ray region

Which of the following is a semiconductor?

• Copper

• Silicon

• Mica

• Glass

In the photoelectric effect, stopping potential is directly proportional to:

• Intensity of light

• Frequency of light

• Wavelength of light

• Work function