Which of the following does  notaccurately describe transistors?                 a.  both npn and pnp transistors consist of an emitter, base, and collector.      b.  both npn and pnp transistors consist of a base composed of an n-type material.      c.  both npn and pnp transistors consist of p-type and n-type material.      d.  both npn and pnp transistors operate in the same manner but with interchanged terminals and opposite directions of voltage and current. 

Suppose that a mass of 2 kg is attached a spring whose spring constant is 50. the system is damped such that b = 12 . the mass is set in motion with an initial velocity of -8 m/s at a position 0 meters from equilibrium. set up and solve a differential equation that models this motion. write your solution in the form a cos ( ω t − α ) where α is a positive number. use your solution to fill in the information below: what is the amplitude of the motion? what is the value of ω ? what is the phase shift?