An 30.0 N wooden block is pulled across a horizontal wooden floor at a constant velocity. What is the magnitude of the force of kinetic friction
between the block and the floor? [p = 0.30 for wood and wood] *
A. 4N
B. IN
C. 12 N
0 D. 15

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?