A sledgehammer with a mass of 10 kg is used to drive a spike into wood. The spike has a
mass of 1 kg. The blow from the sledgehammer exrts a force of 1000 N downward on the
spike.
What force does the spike exert upward on
the sledgehammer?

8.29 two streams containing pyridine and acetic acid at 25°c are mixed and fed into a heat exchanger. due to the heat-of-mixing effect, it is desired to reduce the temperature after mixing to 25°c using a stream of chilled ethylene glycol as indicated in the diagram. calculate the mass flow rate of ethylene glycol needed. the heat capacity of ethylene glycol at these conditions is approximately 2.8 kj/(kg k), and the enthalpy change of mixing (δmixh) is given below.