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A body receives 400 J of incident radiation. Of this, 20% is reflected and 120 J is absorbed. What percentage of the incident radiation is transmitted?

1. 10
2. 15
3. 25
4. 50

Correct answer: 50

Solution

Reflected = 20% (80 J) and absorbed = 120 J = 30%; transmitted = 100% - 20% - 30% = 50%.

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