**Simon Flynn** in his book, “

*The science Magpie*” published in 2012, describes an experiment to determine the speed of light without stepping out of the house. What you need is only a microwave oven and a suitable food item.

*(inquiries: click here)* **Fig. Stop the rotation; spots appear on food. **

Microwave cooker produces electromagnetic waves which are in the same nature as light. There is an established formula that the velocity (speed) of a wave can be obtained by multiplying the frequency of a wave by it’s wave length. **V = f l **

( V – velocity , f – frequency and l - wave length

The frequency of the microwaves would be given at the back of the appliance. Normally it would be MHz. This can be converted to Hertz as 2450 X 10 ^{6}

After removing the rotating plate place a chocolate bar and awitch on the oven for 15 seconds. Choclate bar will melt at a few spots.

Measure the distance between the spots. Convert this to meters.

If the measured length was 4 cm conversion will give 0.04 m as half a wave length.

Then the wave length will be 2x 0.04 m = 0.08 m

As the high heat is at the peaks of the wave the distance between the marks will be half a wave length. Double this to get the wave length and apply the formula V = fl.

Velocity = distance x2 x 2450 000 000 m/s

If the measured average value is 6 cm the wave length will be 0.12m

Then V = 0.12 x 2450 000 000 m/s

294 000 000 m/s which is a fair answer compared with the true speed.

The true speed of light = **299 792 458 m/s **