Example no 12
how to know the direction whether to take positive or negative sign?
...
Answers: 3
Physics, 22.06.2019 02:00
In which of the following cases is work being done on an object? question 2 options: pushing against a locked door carrying a box down a corridor pulling a trailer up a hill suspending a heavy weight with a strong chain
Answers: 2
Physics, 22.06.2019 06:00
Which of the following changes will result in a stronger electromagnet? a. using fewer coils of wire b. using a higher voltage c. using a shorter nail d. using a longer wire
Answers: 1
Physics, 22.06.2019 06:20
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?
Answers: 1
Physics, 22.06.2019 12:30
An ice-making machine inside a refrigerator operates in a carnot cycle. it takes heat from liquid water at 0.0 degrees celsius and rejects heat to a room at a temperature of 19.2 degrees celsius. suppose that liquid water with a mass of 76.3kg at 0.0 degrees celsius is converted to ice at the same temperature. take the heat of fusion for water to be l_f = 3.34*10^5 j/kg.how much energy e must be supplied to the device? express your answer in joules.
Answers: 1
Biology, 08.05.2020 09:57
Mathematics, 08.05.2020 10:57
Mathematics, 08.05.2020 10:57
Chemistry, 08.05.2020 10:57
Mathematics, 08.05.2020 10:57
Mathematics, 08.05.2020 10:57
Social Studies, 08.05.2020 10:57
Biology, 08.05.2020 10:57
Mathematics, 08.05.2020 10:57
History, 08.05.2020 10:57