Magnets have a force called magnetism that attracts iron and steel. The Earth acts like a giant magnet due to the swirling iron in its core, which is what gives us gravity. Sound is vibration through air that cannot be heard in a vacuum. Resonance causes an object to naturally vibrate at its frequency, and can be sped up or slowed down. Lodestones were rocks that attracted or repelled each other, demonstrating early magnetism. The frequency of sound waves determines if it is high or low pitch, with more rapid waves creating higher sounds. Echoes are the reflection of sounds off hard surfaces in enclosed spaces. A magnetic field is the area around a magnet where its effects are detectable, weakening further
2. Is an invisible force that draws together some metals : iron and steel. This force is specially strong at each end of the magnet ( north and south)
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4. SOUND Vibration through air If you can´t hear any sounds in a vacuum
5. Resonance An object always tends to vibrate freely at the same rate this natural frequency. The vibration can be faster or slower by jogging it at particular intervals.
7. SOUND FREQUENCY The difference is the frequency of the sound waves. If a sound waves follow very rapidly one after another, they are high-frequency and make a high sound. If there are low-frequency there will be a low sound.
8. Echo Is the sound of your voice bouncing back from the walls. Echoes only bounce back clearly off smooth,hard surfaces, and in confined spaces.
9. MAGNETIC FIELD The area around the magnet in which its effects are felt. It gets gradually weaker farther away from the magnet.
