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Why does CONDUCTION require a MEDIUM while RADIATION does NOT?
A{'text': 'Conduction is faster', 'label': 'A'}
B{'text': 'Conduction is molecular/diffusion phenomenon — needs molecules to collide; radiation is electromagnetic waves that can travel through vacuum', 'label': 'B'}
C{'text': 'Both require a medium', 'label': 'C'}
D{'text': 'Conduction is always faster than radiation', 'label': 'D'}
Answer & Solution
Correct answer: B. {'text': 'Conduction is molecular/diffusion phenomenon — needs molecules to collide; radiation is electromagnetic waves that can travel through vacuum', 'label': 'B'}
Conduction occurs by molecular diffusion (vibrations in solids, collisions in gases/liquids). No molecules = no conduction (vacuum stops it). Radiation = EM waves, propagate through vacuum (sunlight reaches Earth across space).
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