A block made of iron with a mass of 0.80 kg is heated to 800∘C, then dropped into 5.00 kg of water at 10∘C. What is the total change in entropy (in J/K ) of the block-water system, assuming no energy is lost by heat from this system to the surroundings? The specific heat of iron is 448 J/(kg⋅K), and the specific heat of water is 4,186 J/(kg⋅K). (Hint: note that dQ = mcdT.) J/K
![A firearm can be modeled as a kind of heat engine, where the projectile acts as a piston that separates from the rest of the system during expansion. Consider a gun with a 1.60 kg barrel made of iron [specific heat = 448 J/(kg⋅∘C)]. The gun fires a 3.40 g bullet that exits the barrel with a speed of 340 m/s. When the propellant is ignited, 1.10% of the energy released goes into propelling the bullet (this is the thermal efficiency of the "engine"). The other 98.9% can be approximated as being entirely absorbed by the barrel, which increases in temperature uniformly for a short time before this energy is dissipated into the surroundings. What is this temperature increase (in ∘C)? (Round your answer to at least one decimal place.) ∘C](https://www.doubtrix.com/uploads/editor/3573972417MJHpmUZauf.png)
