Question

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 energy decreases by 5.46 x 104 J. Determine each of the following quantities (including the algebraic sign): (a)W, (b)U, and (c)Q.

Answer 1

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

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