Volcanic and other such activity at the mid-atlantic ridge extrudes material to fill the gap between separating tectonic plates associated with continental drift. the magnetization of rocks is found to reverse in a coordinated manner with distance from the ridge. what does this imply about the earth’s magnetic field and how could the knowledge of the spreading rate be used to give its historical record?

Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 18oc and exits at 6.0 bar. the refrigerant undergoes a throttling process. determine the temperature, in oc, and the quality of the refrigerant at the exit of the expansion valve.

Science and technology are interdependent. advances in one lead to advances in the other. give an example of this phenomenon.

Boxing gloves are padded to lessen the force of a blow. (a) calculate the force exerted by a boxing glove on an opponent’s face, if the glove and face compress 7.50 cm during a blow in which the 7.00-kg arm and glove are brought to rest from an initial speed of 10.0 m/s. (b) calculate the force exerted by an identical blow in the gory old days when no gloves were used and the knuckles and face would compress only 2.00 cm. (c) discuss the magnitude of the force with glove on. does it seem high enough to cause damage even though it is lower than the force with no glove?