A smoke detector is an electronic fire-protection device that automatically senses the presence of smoke as a key indicator of fire and creates a loud sound as a warning. In 3-5 sentences, describe what is happening inside a photoelectric smoke detector as soon as smoke enters it

The magnitude of the amount of energy released by burning a fuel source, measured in energy per unit mass, is called its fuel value. note that the fuel value is the negative of the isobaric specific heat of combustion for the fuel. if all the energy obtained from burning 1.23 pounds of butane with a fuel value of 10.85 kcal/g is used to heat 128.0 kg of water at an initial temperature of 18.3 °c, what is the final temperature? note that 1 lb = 453.6 g.