Final answer:
The terms px and ex refer to different physical quantities depending on the context; px could be the x-component of momentum, and ex could be the expected value or the x-component of an electric field. Calculations would vary based on whether the context is statistical mechanics, electric fields, quantum mechanics, or classical mechanics. The specific formula or signal given in each case will dictate how the values are calculated.
Step-by-step explanation:
To determine the value of px and ex for each signal mentioned, we must first understand what these symbols represent within the given context of physics problems. The term Ex often represents expected value or summation of certain quantities in statistical mechanics or quantum mechanics.
For the signal described by EX ~ N[(80)(90), (√80)(15)], we are dealing with a normal distribution where µx is the mean, σx is the standard deviation, and n is the number of values. Thus, Ex would refer to the expected sum of the 80 values in the distribution.
In the context of electric fields, px could refer to the x-component of a vector such as momentum (p), and ex could be the x-component of the electric field (E). For the signal Ex = (10 N/C) sin (20x - 500t), this is a function representing an electric field's variation over space and time.
In quantum mechanics, the expectation value ex of a particle's position might be given by a complex formula involving wave functions, such as -α x-i E t/h Axex, where specific calculations would be required to derive physical observables.
Finally, in mechanics, px and ex could represent the x-components of momentum and position, respectively, before or after specific events such as collisions.