A pure sample of atomic gas has atoms with six principal quantum numbers that can yield several emission lines. What is the number of possible electron shell transitions for which energy is radiated? (Hint: if an electron has jumped form n = 1 to n = 6, it can have these transitions: n=6 to n=5, n=6 to n=4, n=6 to n=3, n=6 to n=2, n=6 to n=1. That's 5 of them – can you find the rest? Remember, the electron didn't have to jump all the way to the n=6 level to start out with.) 12 9 15 14

Clothing made of several thin layers of fabric with trapped air in between, often called ski clothing, is commonly used in cold climates because it is light, fashionable, and a very effective thermal insulator. so it is no surprise that such clothing has largely replaced thickand heavy old-fashioned coats. (a) consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 w/m·°c) with 1.5-mm-thick air space (k = 0.026 w/m·°c) between the layers. assuming the inner surface temperature of the jacket to be 28°c and the surface area to be 1.25 m2, determine the rate of heat loss through the jacket when the temperature of the outdoors is 0°c and the heat transfer coefficient at the outer surface is 25 w/m2·°c. (b) what would your response be if the jacket is made of a single layer of 0.5-mm-thick synthetic fabric? what should be the thickness of a wool fabric (k = 0.035 w/m·°c) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket?

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?