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In a new system of units, the unit of mass is 2 kg, the unit of length is 4 m, and the unit of time is 2 s. How many joules correspond to 1 unit of energy in this new system?

1. 8 J
2. 16 J
3. 32 J
4. 64 J

Correct answer: 16 J

Solution

Energy = M*L²*T^(-2). Substituting new units: 1 unit of energy = (2 kg)*(4 m)²*(2 s)^(-2).

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