Answer and explain reasoning for each part
when food is cooked in a pressure cooker,
why is it very important to cool the container with cold water before attempting to remove the lid? explain your reasoning.
b. would you dare to place your bare hand about 1 foot above the steam coming out of the cooker’s vent pipe? why, or why not?
c. would you dare to place your bare hand about 1 inch above the steam coming out of the cooker’s vent pipe? why, or why not?

What is the energy of a photon of ultraviolet radiation with a frequency of 4.4 × 1015 hz? planck’s constant is 6.63 × 10–34

4r-134a enters the condenser of a residential heat pump at 800 kpa and 50°c at a rate of 0.022 kg/s and leaves at 750 kpa subcooled by 3°c. the refrigerant enters the compressor at 200 kpa superheated by 4°c determine (a) the isentropic efficiency of the compressor, (b) the rate of heat supplied to the heated room, and (c) the cop of the heat pump. also, determine (d) the cop and rate of heat supplied to the heated room if this heat pump operated on the ideal vapor-compression cycle between the pressure limits of 200 and 800 kpa. (0.757, 4.37 kw, 5.12, 6.18, 3.91 kw)

The discovery of the electron as a subatomic particle was a result of