Using si units, calculate the change in potential energy of a 150-lb person riding the 15 ft long uphill portion of a water slide. the change in potential energy is defined as mgah where ? h is the change in vertical height. the uphill portion of the slide is set at an angle of 45°

The faster the cooling rate the higher the hardness (in steels). Water-quenched steels will generally be harder than oil-quenched steels. This is mainly because the thermal conductivity of water is higher than the thermal conductivity of most oils (that I know); consequently, the rates of cooling will be less rapid (or lower) in oils compared with water. Also, see TTT and CCT phase diagrams for more information (if you haven't done so already).