Any motion that repeats itself in equal intervals of time is called periodic motion.
Examples: The spin of earth, the motion of the moon round the earth etc.,
If a particle in periodic motion moves back and forth. OVer the same path, we call the motion oscillatory or vibratory.
Eg: The oscillations of the balance wheel of a watch, a violin string, a mass attached to a spring, air molecules as a sound wave passes by.
Not only mechanical system oscillate Radio waves, microwaves and visible light are
oscillating magnetic and electric field vectors.
When the periodic motion is about a point along a straight line, it is known as Simple
Harmonic Motion (S.H.M).
Thus S.H.M is a special case of periodic motion.
Simple Harmonic Motion (S.H.M) is defined as the motion of a particle in a straight
line about a mean position, such that the force acting on the particle is always directed
towards that mean point and the force is proportional to the distance of the particle
from the mean position.
--> The periodic motion of a particle is said to be SHM, if
(i) The motion of a particle is vibratory about a mean position.
(ii) The acceleration of the particle is always directed towards the mean position.
(iii) The magnitude of the acceleration (a) is directly proportional to the displacement.
(x) of the particle from its equilibrium position, that is a∝ – x
--> Hooke's Law is a special case of a more general relation, dealing with the deformation of elastic bodies; discovered by Robert Hooke (1635-1703). It is obeyed by springs and other elastic bodies provided the deformation is not too great. Hooke's Law holds almost up to the elastic limit for many common materials.
Stress:
The restoring force per unit area, set up inside a body is called stress.
∴ Stress = Restoring Force/ Area
= Deforming Force / Area
= F/A
Strain:
The ratio of change produced in the dimensions of a body by a system of forces or couples in equilibrium to its original dimensions is called strain.
Hooke's Law:
It states that the stress in a body is directly proportional to the corresponding strainwith proportionality limit.
Examples: The spin of earth, the motion of the moon round the earth etc.,
If a particle in periodic motion moves back and forth. OVer the same path, we call the motion oscillatory or vibratory.
Eg: The oscillations of the balance wheel of a watch, a violin string, a mass attached to a spring, air molecules as a sound wave passes by.
Not only mechanical system oscillate Radio waves, microwaves and visible light are
oscillating magnetic and electric field vectors.
When the periodic motion is about a point along a straight line, it is known as Simple
Harmonic Motion (S.H.M).
Thus S.H.M is a special case of periodic motion.
Simple Harmonic Motion (S.H.M) is defined as the motion of a particle in a straight
line about a mean position, such that the force acting on the particle is always directed
towards that mean point and the force is proportional to the distance of the particle
from the mean position.
--> The periodic motion of a particle is said to be SHM, if
(i) The motion of a particle is vibratory about a mean position.
(ii) The acceleration of the particle is always directed towards the mean position.
(iii) The magnitude of the acceleration (a) is directly proportional to the displacement.
(x) of the particle from its equilibrium position, that is a∝ – x
--> Hooke's Law is a special case of a more general relation, dealing with the deformation of elastic bodies; discovered by Robert Hooke (1635-1703). It is obeyed by springs and other elastic bodies provided the deformation is not too great. Hooke's Law holds almost up to the elastic limit for many common materials.
Stress:
The restoring force per unit area, set up inside a body is called stress.
∴ Stress = Restoring Force/ Area
= Deforming Force / Area
= F/A
Strain:
The ratio of change produced in the dimensions of a body by a system of forces or couples in equilibrium to its original dimensions is called strain.
Hooke's Law:
It states that the stress in a body is directly proportional to the corresponding strainwith proportionality limit.
Stress ∝ Strain
Stress = E x strain
(where E is called modulus of elasticity. Its value depends on the nature of the material, temperature and impurities)
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