Wednesday 3 Nov:

Target Pendulum & periods

Journal

1. A student hangs three identical 100 g masses on a spring, stretching it 10.5 cm.  After coming to rest, the bottom mass falls off (200g still on the spring). 

a)  Calculate the amplitude of oscillation of the remaining masses.

 .105m     (i.e., 10.5cm)

 Amplitude is the farthest point it will reach in its oscillation. If it is stretched 10.5cm then it will oscillate at 10.5cm. Mass makes no difference.   

2.  The spring with toy attached to a platform was compressed x distance and  when released, jumped into the air H height  from rest position.

a) Derive an expression for Height H in

    terms of m, x, k & fundamental constants

a. Change in PE_g  = Stored energy in string

  DPE_g = U_s

mgH = 1/2kx²

H = (kx²) / (2mg)

b. More mass was added to the toy and it released again. What is the relationship between mass and height?

    (Direct or indirect)

indirect