Draw a graph to show the variation of PE, KE and total energy of a simple harmonic oscillator with displacement.
Let us consider that a mass is lying on a horizontal frictionless surface, where spring constant = k.
If we displace the mass by distance A from its mean position, then it will execute SHM.
At this stretched position, P.E. of mass =
Now, at maximum stretch, i.e.,
At x = A, K.E. = 0
Now, at
P.E. = total energy
=
Now let’s consider that the mass is back at its mean position, now the restoring force acting on the particle will be
=
The restoring force constant of oscillator is
When
&
Now, when
x |
K.E. |
P.E. |
T.E. |
0 |
0 |
||
+A |
0 |
||
-A |
0 |
Now, at displacement ‘x’, T.E. will be,
E = K.E. + P.E.
=
Thus, with displacement ‘x’, E is constant.