Monday 8 Nov:

 

Target Gauge Press/Absolute Press

Journal:

 Tripling the amplitude of a vibrating mass-and-spring system produces what effect on the system’s mechanical energy?

 

 

 

 

 

 

 

 

 

 

E = ½ kx2  

 (3X)2 = 9E (9 times the energy)

 

 

 

           

 

 

 

 

 

 

 

1. A pendulum has a length of 2.0m and is on a planet that has twice the gravity as Earth.

What is the: a. Period, b. Frequency

 

 

 

 

 

 

 

 

 

 

 

a. T = 2P √ (L/g)

                T = 2P √ (2/20)

         T =  1.99 s

 

b.  Freq = 1/T à 1/1.99 = .50 HZ

 

2. An uncompressed spring , spring constant 320 N/m is connected to a 200 g mass on a frictionless surface.  If the mass is moved 25 cm from the rest position and released: a. Calculate the speed of the mass as it passes through the initial equilibrium point. b. Frequency  c. Period

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a. KE = Ws  

½ mv2 = ½ kx2

½(.2)(v2) = ½ (320)(.25)2

v2 = (160)(.0625) / .1

V =  √ 100 = 10m/s

 

b. freq = 1/(2P) √ (m/k)

freq = 1/(2P) √ (.2/320)

        freq =  6.37 Hz

       

c. T = 1/f

    T = 1/6.37 à .157s

 

 

3. A particle in SHM passes through two points on pendulum a certain distance apart with the same speed. It takes 3.0sec to get from Point A to Point B. It takes a further 4 seconds to pass through Point B in the opposite direction.

What is the:

a. Period

b. Frequency

      

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  1. T = time for one cycle. Only possible way is:

Pts:    A à B  =                                3s 

                   B à end =                            2s

                        End à B =                            2s

                        B à A =                                 3s

                        A to other end =                  2 s

                        Other end back to A =       2 s

                                    T (period) =             14s

 

b.  Freq = 1/T à 1/14 = .071 HZ