Answer:
The change in internal energy and efficiency are 10000 J and 5.26%.
Explanation:
Given that,
Work = 500 J
Heat transfer = 9500 J
(a). We need to calculate the decrease in her internal energy
Using equation of internal energy of a system
[tex]\Delta U=Q-W[/tex]
Q = heat
W = work done
Put the value into the formula
She looses her heat -9500 J
[tex]\Delta U=-9500-500[/tex]
[tex]\Delta U=-10000\ J[/tex]
(b). We need to calculate the efficiency
Using formula of efficiency
[tex]e=\dfrac{W}{Q}[/tex]
[tex]e=\dfrac{500}{9500}[/tex]
[tex]e=0.0526\times100[/tex]
[tex]e=5.26\%[/tex]
Hence, The change in internal energy and efficiency are 10000 J and 5.26%.
