A hockey player is standing on his skates on a frozen pond when an opposing player, moving with a uniform speed of 4.0 m/s, skates by with the puck. After 2.80 s, the first player makes up his mind to chase his opponent. If he accelerates uniformly at 0.46 m/s2, determine each of the following.(a) How long does it take him to catch his opponent? (Assume the player with the puck remains in motion at constant speed.)1 s(b) How far has he traveled in that time?2 m

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?

An insulated thermos contains 148 g of water at 72.7 ˚c. you put in a 11.7 g ice cube at 0.00 ˚c to form a system of ice + original water. the specific heat of liquid water is 4190 j/kg•k; and the heat of fusion of water is 333 kj/kg. what is the net entropy change of the system from then until the system reaches the final (equilibrium) temperature?

Amother used 150 watts of power to raise a 15 newton object in a time interval of 8.0 seconds. through what vertical distance was the object raised ?