In moving out of a dormitory at the end of the semester, a student does1.6×10^4jof work. in the process, his internal energy decreases by4.2×10^4jdetermine each of the following quantities (including the algebraic sign): (a)w,(b)δu, and (c)q

         W = 1.6 × 10⁴ J , ΔU = - 4.2 x 10⁴ J , Q = - 2.6 x 10⁴ J

Explanation:

given,                                                

Work done by the student          

         W = 1.6 × 10⁴ J                        

decrease in internal energy        

       ΔU = - 4.2 x 10⁴ J                  

Using formula for heat                      

  Q = W + ΔU                                        

  Q = 1.6 × 10⁴ J + ( - 4.2 x 10⁴ J)      

  Q = - 2.6 x 10⁴ J                                    

Hence,                                                              

         W = 1.6 × 10⁴ J , ΔU = - 4.2 x 10⁴ J , Q = - 2.6 x 10⁴ J

a.) is the correct answer.

explanation:

what is the speed of a softball that travels 20m in 2secs

speed = 20/2 = 10 m/s