Question

In an engine, a piston oscillates with simple harmonic motion so that its position varies according to the expression x= 5.0 cos (2t + 3.1416/6 Where x is in centimeter and t is seconds. At t=0, Find a) the position of the particle b) its angular velocity and frequency c)its acceleration d)The period e)the amplitude of the motion

Answer 1

Answer:

a)   x = 4.33 m ,   b)  w = 2 rad / s ,  f = 0.318 Hz ,  c) a = - 17.31 cm / s²,  

d) T =  3.15 s,  e)  A = 5.0 cm

Explanation:

In this exercise on simple harmonic motion we are given the expression for motion

          x = 5 cos (2t + π / 6)

they ask us for t = 0

a) the position of the particle

      x = 5 cos (π / 6)

      x = 4.33 m

remember angles are in radians

 

b) The general form of the equation is

          x = A cos (w t + Ф)

when comparing the two equations

         w = 2 rad / s

angular velocity and frequency are related

          w = 2π f

           f = w / 2π

           f = 2 / 2pi

           f = 0.318 Hz

c) the acceleration is defined by

      a == d²x / dt²

      a = - A w² cos (wt + Ф)

for t = 0 ,  we substitute

      a = - 5,0 2² cos (π / 6)

      a = - 17.31 cm / s²

d) El period is

          T = 1/f

         T= 1/0.318

         T =  3.15 s

e) the amplitude

        A = 5.0 cm