Higher Physics Lab Atomic & Nuclear Physics



Exp- To determine Planck’s Constant by Cs Photocell.

  • Multipurpose electrometer amplifier.
  • Cs photo cell.
  • Multipurpose power supply.
  • Monochromatic light source may be used in many other experiments also.
  • Hexagonal optical bench.
  • Photoelectric effect.
  • Photo cell.
  • Work function.
  • Planck's constant.
  • Photoelectric voltage.
  • Photon energy.

Principle and Working:
Einstein postulated that light consists of a quantum of particles, called photon whose energy E is proportioned to the frequency n, by an equation, E = hn, where h is planck’s constant.
In this experiment, narrow band interference filters are used to select wave length, each filter selects precisely one spectral line from the light of a high pressure mercury lamp. The monochromatic light falls on the cathode of the photocell. A capacitor, connected between cathode and anode of photocell, charged by anode, is used. Electrometer amplifier is used to measure the voltage at capacitor without current.


Cat. No. Item Name Qty.
SE080 Power Supply 12V AC/DC 5Amp 1
SZ010A Photocell 1
SW440 Mercury Light Source 1
SL754 Convex lens in holder 1
SW752 Iris Diaphragm 1
R7901A Set of Color Filters (Indian/Imported) 1
SD003 Electrometer Amplifier 1
SEB15 Capacitor, 100 pF , 630 V 1
SEB38 Push Switch module 1
SE067 Digital multimeter 1
SL214 Optical bench 1
SL436 Transversal Saddle 1
SN203 Flexible plug lead red (50 cm) 1
SN200 Flexible plug lead black(50 cm) 1
SN207 Flexible plug lead Yellow (100 cm) 1
SN206 Flexible plug lead Yellow (50 cm) 2
SN201 Flexible plug lead black(100 cm) 1
SN204 Flexible plug lead Red(100 cm) 1
C4342 Earthing Lead 1

Available on Request
Four Interference Filters (C0449A) instead of Six Color Fiters (R7901A)

Atomic & Nuclear Physics Experiments