A potato cannon has the fuel combusted, generating a lot of heat and pressure, which launch a potato. The combustion process _____ the internal energy, while launching the potato _____ the internal energy of the potato cannon.
- increases, increases
- increases, decreases
- decreases, increases
- decreases, decreases
This is College Physics Answers with Shaun Dychko. In a potato cannon, some fuel is combusted like maybe some hair spray is burned with piezoelectric lighter from a barbecue which I have done and it's fun and it generates a lot of heat and pressure, which launch a potato and the combustion process increases the internal energy because it adds heat. As you know you've Delta U equals heat added to the system minus work done by the system and so the combustion is a positive Q so it is increasing internal energy or as launching the potato means that potato cannon is doing work on the potato and so that makes a positive W which reduces internal energy and so the answer is B.