Question

Imagine you do 4.18 J of work on a system adiabatically, that is to say, without letting it exchange any thermal energy with its surroundings. How much heat, in calories, would you have to put into the system to get the same ΔE, if no mechanical work was done on or by the system at all?

Answer 1

In an adiabatic process, the change in internal energy of the system is equal to the amount of work done. To convert this change in energy from joules to calories, use the conversion factor 1 calorie = 4.18 joules. Therefore, the change in internal energy would be 1 calorie.

Step-by-step explanation:

In an adiabatic process, there is no heat transfer between the system and its surroundings. Therefore, if you do 4.18 J of work on the system adiabatically, the change in internal energy of the system would be equal to the amount of work done. So, the change in internal energy would be 4.18 J.

To convert this change in energy from joules to calories, we can use the conversion factor:

1 calorie = 4.18 joules

Therefore, the change in internal energy would be 4.18 J * (1 cal / 4.18 J) = 1 cal.

Answer 2

Answer:-4.18 J

Step-by-step explanation:

Given

System is adiabatic i.e. no heat is added and removed therefore

`Q=0`

i.e.
`\Delta U+W=0`

`\Delta U=-W`

`\Delta U=-4.18 J`

Now to get same change in internal Energy heat added provided mechanical work is zero

`Q=\Delta U+W`

`W=0`

`Q=-4.18 J`

i.e. 4.18 J of heat is removed from system