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http://www.youtube.com/watch?v=zWKiWaiM3Pw
- short, comprehensive 1 min clip which gives a brief intro to resonance

When does resonance take place?
Resonance can take place when an object vibrates at another objects resonant frequency.
By forcing an oscillation at a range of frequencies, and measure the amplitude at each, the graph would be as follow:
{stuff.png}

This is a wiki created for an ace activity for resonance and I hope that readers would find my wiki interesting and enriching!
Regards,
Lee YanYan Hui 4o107

http://www.youtube.com/watch?v=zWKiWaiM3Pw
- short, comprehensive 1 min clip which gives a brief intro to resonance

What are some harmful effects of resonance?
the sea. We have this problem in Swansea.
In a car crash a passenger may be injured because there chest is thrown hard against the seat belt. the vibration can burst blood vessels. Bruising of the skin or internal organs such as concussion of the brain can be caused because of the vibration of a movement.

How can resonance be applied to benefit us?
Magnetic resonance imaging is a medical imaging technique used in radiology to visualize internal structures of the body in detail WITHOUT cutting the body open
{mri.jpg}

http://en.wikipedia.org/wiki/Magnetic_resonance_imaging
http://www.physicsclassroom.com/class/sound/u11l5a.cfm
http://en.wikipedia.org/wiki/Resonance
http://www.howstuffworks.com/mri.htm
http://www.thephysicsnotes.com/OLD/resonance.html

What are some examples of resonance?
One example is a simple experimental setup. It is a stone held by a string, acting as a pendulum. If I hit the stone at the wrong frequency, it is considered as forced oscillation. But when I hit it at its resonant frequency, it will increase its amplitude.
{set_up.jpg}
One another example is the breaking of glass. Every object has its own resonant frequency and we can hear that frequency by hitting it. When I tap a glass, it will sing its own resonant frequency so the frequency of the sound wave is the frequency of natural oscillation of the glass. Let’s take opera singers for example. How are they able to sing and break the glass? What they are doing is singing at a forced frequency which excites the glass at its own natural resonant frequency which increases its vibrations and amplitude until the glass cannot hold it anymore and breaks.
{glass.png}
Another example of resonance is the microwave oven. The microwave provides energy to the molecules which causes the water molecules to oscillate resulting in the food getting heated up. When a molecule is pushed, the neighbouring molecules could push it back.The natural frequency of this oscillation is about 2 GHz (which is 2 billion times per sec). However, this is only a misconception of resonance as such resonance only occurs in water vapour at much higher frequencies, at about 20 GHz.
{microwave_oven.jpg}
Lastly, a swing is an example of mechanical resonance. It is very easy to keep someone swinging because all that is needed is to replace that little bit of energy that is being lost to friction. As long as your forced frequency exactly or closely matches the resonant frequency of the swing, it will continue or even go higher very easily. In fact, if the two match exactly then the amplitude of the swing can easily become very large very quickly.
{swing.jpg}