21. Nuclear reactor works on the scientific principle
22. Who discovered neutron
23. Wave nature of electron was discovered by
24. Atomicity of charge was discovered by
25. Theory of relativity was discovered by
26. Electric generator works on the scientific principle
27. Size of the nucleus is
28. The scientists who†discovered natural radioactivity belonged to
29. The scientist who discovered x-rays belonged to:
30. The scattering of light by molecules was discovered by
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