What is another metaphor (aside from the fact that a piano can only produce certain notes) that could help someone understand enrgy quantization at the atomic level? Explain your answer. The text it is referring to is: Because protons and electrons in an atom carry opposite charges, they are attracted to each other and thus maintain the boundaries of the atom as a singular closed system. This means that an atom’s energy is quantized, or fixed to a certain amount. Just like a piano can only produce a certain set of notes that correspond to its keys, an atom of a certain element can only contain a certain fixed amount of energy.

During takeoff, the sound intensity level of a jet engine is 170db at a distance of 34 m. what's the sound intensity level at a distance of 1.0 km?

Part f - example: finding two forces (part i) two dimensional dynamics often involves solving for two unknown quantities in two separate equations describing the total force. the block in (figure 1) has a mass m=10kg and is being pulled by a force f on a table with coefficient of static friction îľs=0.3. four forces act on it: the applied force f (directed î¸=30â above the horizontal). the force of gravity fg=mg (directly down, where g=9.8m/s2). the normal force n (directly up). the force of static friction fs (directly left, opposing any potential motion). if we want to find the size of the force necessary to just barely overcome static friction (in which case fs=îľsn), we use the condition that the sum of the forces in both directions must be 0. using some basic trigonometry, we can write this condition out for the forces in both the horizontal and vertical directions, respectively, as: fcosî¸â’îľsn=0 fsinî¸+nâ’mg=0 in order to find the magnitude of force f, we have to solve a system of two equations with both f and the normal force n unknown. use the methods we have learned to find an expression for f in terms of m, g, î¸, and îľs (no n).

What is special about a dc circuit ?