A baseball player hits a baseball, changing its momentum by 15\, \dfrac {\text{kg}\cdot \text m}{\text s}15 s kg⋅m ​ 15, start fraction, start text, k, g, end text, dot, start text, m, end text, divided by, start text, s, end text, end fraction. The net force on the ball is 7{,}100\,\text N7,100N7, comma, 100, start text, N, end text.

Which property of fossils allow scientists to determine the relative rock ages..

Na food processing facility, a spherical container of inner radius r1 5 40 cm, outer radius r2 5 41 cm, and ther- mal conductivity k 5 1.5 w/m · k is used to store hot water and to keep it at 100°c at all times. to accomplish this, the outer surface of the container is wrapped with a 800-w electric strip heater and then insulated. the temperature of the inner surface of the container is observed to be nearly 120°c at all times. as- suming 10 percent of the heat generated in the heater is lost through the insulation, (a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the container, (b) obtain a relation for the variation of temperature in the container material by solving the differential equation, and (c) evaluate the outer surface tempera- ture of the container. also determine how much water at 100°c this tank can supply steadily if the cold water enters at 20°c.

As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is 100) a) static friction. b) kinetic friction. c) a combination of static and kinetic friction. d) neither static nor kinetic friction, but some other type of friction. e) it is impossible to tell what type of friction acts in this situation.