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Benifits of yoga

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Now days Because of menatal stress lack of physical exercise and lack of time due work  most of the people affect of many kinds of disorders   because of this we have to need regular exercise  and yoga  to overcome this and be healthy by physicaly and mentaly Yoga offers numerous benefits for both the mind and body. Here are some of the key benefits of practicing yoga: Physical Fitness:  Yoga improves strength, flexibility, balance, and stamina. It helps tone the muscles and increases overall physical fitness. Regular practice can lead to improved posture and alignment. Stress Reduction:  Yoga incorporates breathing exercises and meditation, which can help calm the mind and reduce stress levels. It promotes relaxation and provides a sense of inner peace. Mental Clarity:  The combination of physical movement, breath control, and mindfulness in yoga can enhance mental clarity, focus, and concentration. It can also improve memory and cogni...
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Transformer Action of Middle EAR | Machanism of Hearing

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The sound signal that reach to the ear drum in the form of air vibration must be transmitted to the cochlea which is a fluid filled system' 

The impedance of cochlear fluids are much greater then the impedance of air:

Most of the sound energy reflected back  only about 0.1% of the energy transmitted to the cochlea and 99.9% if the energy is reflected back

The middle ear overcome this impedance mismatch by acting as a mechanical transformer that boost the signal so that energy can be effectively transmitted to the cochlea

There are three mechanism which are used to overcome the transformer action of middle ear

1-Area ratio of Ear drum to Oval window 2-Curved membrane buckling effect of the tympanic membrane 3- Lever action of the ossicular chain

1. The Ratio of Ear drum to Oval window

The largest contributions comes from Area advantages' The Area of tympanic membrane larger than the Area of Oval window , The force that us exerted over the larger area of tympanic membrane is transmitted to the smaller area of oval window 



p=F/A        Pressure=Force/Area

The Area of the eardrum =85mm2 only two third of this area can vibrate effectively (Bekesy in 1960)   

The effective Area of eardrum 55mm2 and  Area of oval window 3.2mm2  p=F/A  55/3.2=17.2



2. Curved membrane buckling effects

In the curved membrane buckling mechanism The ear drum curves from  both ends and attached to the manubrium towards the middle ear  

As a results ear drum vibration involves greater displacement bat the curved membrane and less displacement at manubrium  , It follows factor 2 mechanism 

(f1d1=f2d2)

3. Lever action of ossicular chain

Malleus constitute the larger leg of this lever and the Incus is the shortest leg as well as the axis of Rotation 



THE OSSICULLAR RATIO:-

The  size of malleus 9mm and the size of incus is 7mm  than the  9/7=1.3

TOTAL TARSFORMER ACTION OF MIDDLE EAR:-   17.2×1.3×2=44.7

20 log (44.7/1)=33dB

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