Answer : The final energy of the system if the initial energy was 2000 J is, 3500 J
Solution :
(1) The equation used is,
![\Delta U=q+w\\\\U_(final)-U_(initial)=q+w](https://img.qammunity.org/2020/formulas/chemistry/middle-school/d6hg0rdvneb6s4ia2lq6c9whgib35up7n1.png)
where,
= final internal energy
= initial internal energy
q = heat energy
w = work done
(2) The known variables are, q, w and
![U_(initial)](https://img.qammunity.org/2020/formulas/chemistry/middle-school/idp2qq5begfj5j5ajx9wxgluwjo4707blp.png)
initial internal energy =
= 2000 J
heat energy = q = 1000 J
work done = w = 500 J
(3) Now plug the numbers into the equation, we get
![U_(final)-(2000J)=(1000J)+(500J)](https://img.qammunity.org/2020/formulas/chemistry/middle-school/1q8qm0ul8ztncbyqtxw6hvi6sub2l5vdby.png)
(4) By solving the terms, we get
![U_(final)-(2000J)=(1000J)+(500J)](https://img.qammunity.org/2020/formulas/chemistry/middle-school/1q8qm0ul8ztncbyqtxw6hvi6sub2l5vdby.png)
![U_(final)-(2000J)=1500J](https://img.qammunity.org/2020/formulas/chemistry/middle-school/wm5banps7mqn9l3812x6uma4all5u5zoyr.png)
![U_(final)=2000J+1500J](https://img.qammunity.org/2020/formulas/chemistry/middle-school/okr2dhgumlwtv2m8i5y2q2g3oxx6ps471u.png)
![U_(final)=3500J](https://img.qammunity.org/2020/formulas/chemistry/middle-school/2irtkekluwz55w7ny9bexhzihenqlab021.png)
(5) Therefore, the final energy of the system if the initial energy was 2000 J is, 3500 J