study material-physics-mechanics-shm superposition
SHM -2
Now suppose the ball started from a point after than
= 0 say
then :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_4.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_003.gif)
So here
= phase constant
# illustration :-
Two SHM's of amplitude
with initial hase constanta as
start with angular velocities w and 4w respectively. Find the time after which they are in phase.
Question:-
That they are in phase.
Solution :- "In phase" means having same phase. Which means they are at the same position instant & their velocities are also in same direction.
* Tip The problem can be solved easily using two techniques : (1) circle method for SHM
(2) Relative Concept.
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_6.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_028.gif)
Initial angle between two =![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_017.gif)
So time taken =![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_030.gif)
Dumb Question : Is only the functiony =
SHM?
Solution :- No, any function which satiesfies the condition that if y = y(t); then
, can represent the SHM.
Accelaration and velocity in SHM :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_019.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_7.gif)
if
= 0 and ![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_009.gif)
The graphs if drawn are :-
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_8.gif)
[of
= 0] . All v, y, w have different Amplitude.
Differential Equation of accelation of particle SHM is
# Illustration : If equation of a motion is
Show that it is SHM and find maximum accelaration and maximum velocity.
Solution :-
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_020.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_016.gif)
Hence it is SHM.
Now
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_010.gif)
* Energy terms in SHM :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_021.gif)
(a) Kinetic Energy :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_005.gif)
(b) Potential Energy :![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_022.gif)
Derivation : Work done by Force F during displacement from x to x + d is
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_007.gif)
Integrate both sides
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_024.gif)
Now
Potential Energy = - Work Done by force.
So,![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_012.gif)
Let at![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_025.gif)
So![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_002.gif)
So total Energy in SHM :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_008.gif)
for a particular SHM with w
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_011.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_023.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_4.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_003.gif)
So here
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_023.gif)
# illustration :-
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_5.gif)
Two SHM's of amplitude
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_018.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_027.gif)
Question:-
That they are in phase.
Solution :- "In phase" means having same phase. Which means they are at the same position instant & their velocities are also in same direction.
* Tip The problem can be solved easily using two techniques : (1) circle method for SHM
(2) Relative Concept.
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_6.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_028.gif)
Initial angle between two =
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_017.gif)
So time taken =
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_030.gif)
Dumb Question : Is only the functiony =
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_015.gif)
Solution :- No, any function which satiesfies the condition that if y = y(t); then
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1.gif)
Accelaration and velocity in SHM :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_019.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_7.gif)
if
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_014.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_009.gif)
The graphs if drawn are :-
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/SHM_Dia_8.gif)
[of
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_006.gif)
Differential Equation of accelation of particle SHM is
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_026.gif)
# Illustration : If equation of a motion is
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_029.gif)
Solution :-
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_020.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_016.gif)
Hence it is SHM.
Now
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_010.gif)
* Energy terms in SHM :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_021.gif)
(a) Kinetic Energy :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_005.gif)
(b) Potential Energy :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_022.gif)
Derivation : Work done by Force F during displacement from x to x + d is
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_007.gif)
Integrate both sides
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_024.gif)
Now
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_004.gif)
So,
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_012.gif)
Let at
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_025.gif)
So
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_002.gif)
So total Energy in SHM :
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_008.gif)
![](/images/1/subjects/physics/simple-harmonic-motion-2_files/Simple_1_013.gif)