Se tienen 145 g de etanol (C2H5OH) a -273°C, sabiendo que la temperatura de fusión del mismo es de -117°C, su Hfus = 5.02 KJ/mol (calor latente de fusión), su temperatura de vaporización es 78°C y su Hvapor = 39.3 KJ/mol, determinar cuanta energía requiere para llegar a una temperatura de 100°C. (Cetanol = 112 J/mol K)

Mass (kg) force (n) 5 25 10 50 15 75 20 100 a student was trying to find the relationship between mass and force. he placed four different masses on a table and pulled them using a spring scale. the table shows the different masses used in the experiment and the force required to pull each mass. the student concluded that more force was required to pull heavier objects. what comment would you make regarding his conclusion? a) no clear relation can be observed between mass and force from the data. b) there is a direct proportion between the mass and force listed in the table. c) gravity should have been taken into account while performing the experiment. d) there is an inverse proportion between the mass and force listed in the table.

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.