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Fed [463]
3 years ago
15

In moving out of a dormitory at the end of the semester, a student does 1.20 x 104 J of work. In the process, his internal energ

y decreases by 5.46 x 104 J. Determine each of the following quantities (including the algebraic sign): (a)W, (b)U, and (c)Q.
Physics
1 answer:
Zielflug [23.3K]3 years ago
8 0

Answer:

(a) W=1.20×10⁴J

(b) U= -5.46×10⁴J

(c) Q= -4.26×10⁴J

Explanation:

Given that student does 1.20×10⁴J work

(a) W=1.20×10⁴J

Work done by student,so positive sign

During the process, his internal energy decreases by 5.46×10⁴J.

(b) U= -5.46×10⁴J.

As the Energy decreases therefore negative sign

For (c) Q

We know the formula

Q=W+U\\Q=1.2*10^{4}+(-5.46*10^{4} )\\ Q=-4.26*10^{4}J

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