Specific Latent heat 1. (a) The melting point and boiling point of lead are 327 and 1774 degrees Celsius
and -219 and -183 for Oxygen.
(i) At - 200 °C will the oxygen be a solid, liquid, or gas?
(ii) At 450 °C will the lead be a solid, liquid, or gas?
(b) The graph shown alongside shows how the temperature of a pure substance
changes as it is heated.

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.

Emmy kicks a soccer ball up at an angle of 45° over a level field. she watches the ball's trajectory and notices that it lands, two seconds after being kicked, about 20 m away to the north. assume that air resistance is negligible, and plot the horizontal and vertical components of the ball's velocity as a function of time. consider only the time that the ball is in the air, after being kicked but before landing. take "north" and "up" as the positive ‑ and ‑directions, respectively, and use ≈10 m/s2 for the downward acceleration due to gravity.

The diagram shows a boulder rolling down a hill into a valley and then up the opposite hill. at which position does the boulder have the greatest kinetic energy? ab c d