Air enters the turbine of a gas turbine at 1200 kPa, 1200 K, and expands to 100 kPa in two stages. Between the stages, the air is reheated at a constant pressure of 350 kPa to 1200 K. The expansion through each turbine stage is isentropic. Determine, in kJ per kg of air flowing, a. the work developed by each stage. b. the heat transfer for the reheat process. c. the increase in net work as compared to a single stage of ex- pansion with no reheat.

A0.580-kg rock is tied to the end of a string and is swung in a circle with a radius of 0.500 meters. the velocity of the rock is 4.50 m/s. what is the centripetal force acting on the rock? 15.5 n 5.22 n 69.8 n 23.5 n

On a horizontal frictionless surface, a small block with mass 0.200 kg has a collision with a block of mass 0.400 kg. immediately after the collision, the 0.200 kg block is moving at 12.0 m/s in the direction 30° north of east and the 0.400 kg block is moving at 11.2 m/s in the direction 53.1° south of east. use coordinates where the +x-axis is east and the +y-axis is north.(a) what is the total kinetic energy of the two blocks after the collision (in ) what is the x-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your ) what is the y-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your answer.)

What are known as the properties of substances that describe a substance et does not change that substances?