Speed of light measurement

  Date of measure: 06.05.2019 

Tools

• alternating voltage generator with high frequency
• two long copper conductors
• fluorescent lamp
• probe to determine the voltage antinode
• length gauge

Description of measurement method

• connect two long conductors to alternating voltage generator with high frequency
• standing wave is formed around the long conductors

• use the probe to determine the position of antinode
• measure the position of antinodes
• we calculate wavelength and speed of light

Our measurement:

Generator has a frequency f = 433,92 MHz = 433 920 000 Hz

Standing wave is formed around the long conductors. You can see antinodes and nodes in the picture.

We use a probe to determine the position of antinodes.

We measure the distance of antinodes and we measure the speed of light.

c = λf

Conclusion:

Speed of light is

Really value speed of light in air is 299 879 398 m.s-1.

The End