Question #f3570

1 Answer
Aug 10, 2015

Dependent on amplitude and
Conserved

Explanation:

Mechanical energy is the sum of Kinetic energy and Potential energy.
E_o=K+U

Imagine an object moving in a circle with constant angular velocity, omega.

Let displacement, x=Asin(omegat)
v=(dx)/(dt)=Aomegacos(omegat)

The kinetic energy,K is 1/2mv^2= 1/2mA^2omega^2cos^2(omegat)
Maximum kinetic energy will be accompanied by zero potential energy:
E_o=K_max+U_min
=K_max
Therefore, K_max=1/2mA^2omega^2cos^2(2pi)=1/2mA^2omega^2
and since E_o=K_max,

E_o=1/2mA^2omega^2

From the equation above, I conclude that mechanical energy is:

  • Dependent on amplitude
  • Dependent on mass
  • Conserved (E_o is just a multiplication of constants as derived above)