Science in School

Table near the projector with power generator + Light box (with single slit) and wavy Perspex block (with white A4 paper underneath) Camera connected to projector to show the Perspex demo. Scientists wearing lab coats one has comb in his pocket. Act 3. Lap top. CRO + Signal generator. Safety glasses (x2) + Lab coats (x3) Test tubes + test tube ... ................
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