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speed-of-light

SPEED/VELOCITY OF LIGHT EXPERIMENT

Item Code : SK077

Principle and Working:

The LASER beam from the transmitter strikes the beam splitter, which splits the beam into two perpendicular directions. The first beam is transmitted directly through the transmitter and is received in the first channel of the receiver.
The second perpendicular beam from the beam splitter travels a longer distance by being reflected from a mirror placed about 5 meters away or more and is then received in the second channel of the receiver.In the present setup, the time difference between the two peaks of the received LASER signals can be observed on an oscilloscope (>40 MHz) and used to calculate the speed/velocity of light.

  • 1MHz internal modulation frequency.
  • Dual Photo Detector built-in single assembly.
  • Transmitter and Receiver with Low Power Consumption (5V DC, 1A).
  • To determine the Speed of Light in air.
  • Laser transmitter :Peak wavelength 635nm, Modulation frequency 1MHz, output BNC (F), voltage 5V DC, current 250mA, optical power 0.4 to 0.8mW, Laser Class II, operating temp. 0 to 40°C, storage temp. -10 to 50°C.
  • Laser receiver :Photo detector (BPW34) Silicon PIN Photo-diode, Reverse voltage 32V, Max. current 30nA, Peak wavelength 850nm, Rise time 20ns, Fall time 20ns, Angle 60°, Photo current 80uA, Power dissipation 150mW, Responsivity 0.62A/W, Radiant sensitive area 2.65 x 2.65mm (LxW), output BNC (F), Operating voltage : 5V DC.
  • Beam splitter :Size 50x50x10mm, R:T 50:50%, Surface λ/5 Mounting rod 10mm diameter.
  • Reflecting mirror :Size 50x50x6mm, Surface λ/5, Mounting Rod 10mm diameter.
S.No.Item NameSK077
1Reflecting Mirror with Mount1
2MS Rod D-10 mm, L-1000mm1
3Laser Transmitter Module for SK0771
4Laser Receiver Module for SK0771
5Beam Splitter1
6Stand Base, A- Shaped1
7Convex Lens in Holder FL-5 cm2
8Boss Head Square1
9Measuring Tape1
10Cylindrical base5
11Adaptor 5 Volt, 1A2
12BNC CABLE2
13Digital Storage Oscilloscope 30MHz (Optional)1