امواج، بصریات اور جدید طبیعیات

In Young's double slit experiment, if the wavelength of light is doubled, the fringe spacing:

• 1 Stays the same
• 2 Doubles
• 3 Halves
• 4 Becomes zero

Two tuning forks of 256 Hz and 260 Hz are sounded together. What is the beat frequency?

• 1 2 Hz
• 2 516 Hz
• 3 4 Hz
• 4 258 Hz

If the momentum of a particle is doubled, its de Broglie wavelength:

• 1 Becomes four times larger
• 2 Is halved
• 3 Doubles
• 4 Stays the same

A metal has a work function of 2 eV and is lit by photons of 5 eV. What is the maximum kinetic energy of the emitted electrons?

• 1 7 eV
• 2 3 eV
• 3 2 eV
• 4 5 eV

What is the fundamental frequency of a pipe of length 0.5 m closed at one end? (Speed of sound 340 m/s)

• 1 85 Hz
• 2 680 Hz
• 3 170 Hz
• 4 340 Hz

A sample has 800 radioactive nuclei. How many remain undecayed after 2 half-lives?

• 1 600
• 2 200
• 3 100
• 4 400

Polarisation of light shows that light is:

• 1 A sound wave
• 2 A longitudinal wave
• 3 A transverse wave
• 4 A particle only