Aperson travels by car from one city to another. she drives for 23.5 min at 74.5 km/h, 15.9 min at 111 km/h, 49.2 min at 38.7 km/h, and spends 17.3 min along the way eating lunch and buying gas. determine the distance between the cities along this route. answer in units of km.

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?

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

The first law of thermodynamics states that heat added to a system is neither created nor destroyed but is as it changes into other forms of energy.