Sunday, May 6, 2012

My Sound Experiment

Hi there ! Today I am going to tell you about my experiment about sound. The experiment is making the telephone. We were working in pairs. First we were asked to make a hole at the bottom of the plastic cup. Then, we put the strings between them. Then we pant the plastic cup and tried the experiment. Finally we therefore conclude that sound will travel faster through string than through the air.

Here are some pictures of the experiment :


Let's Find Out about Sound !!!

Let's Find Out about Sound !!!!!!!!!

What is sound ?
Sound is an amount of vibration that enters our ears. 

How does sound travels ? 

Sound travels in all directions. When an object produces sound, the sound travels away from the object in all directions. Sound can travel through water and air. 

What is sound wave ? 

Sound wave is the squezing and strechting of sound.

How do we hear sound , and how might it affect hearing ?
Sound waves travel to the air and enters the ear drum and allows it to vibrate.
To much loudness might affect our hearing or can cause us deafness.



How do sound transfer to the inner drums ?

The incoming sound waves that are sent to the eardrum cause it to vibrate. These vibrations in turn cause movement in three small bones called ossides, that are connected to the inner ear.

Sound travels away from the source

When we drop a small pebble into a pond, we can see ripples on the surface of the water. These ripples travel away from the pebble in all directions.

When an object produces a sound, the sound travels away from the object in all directions. Object that produced sound is called source of the sound.

The loudness of the sound decreases as the sound travels farther away from the source. When we are very close to the source of the sound, it becames loud. When we move away from the source of the sound, the sound becames softer.

Sound requires a medium to travel 

Sound requires medium to travel. When an alarm clock rings, we can hear the sound because the sounds travels through the air reaches our ears. In this case, air is the medium through which sound travels.

A space has no matter in it is called a vacumm. Vacumm can be created in an empty jar by sucking out all the air from it. We cannot hear an alarm clock when it rings inside a jar with a vacumm because there is no air or any other medium through which the sound travels. 
 
Sound can travel through solid, liquid or gaseous material. Travels at different speeds in different media.

Sound travels in all directions. Sound travels faster through most solids and liquids than in the air. It is why we can hear the other person talking into the tin can at the other end of the tin can telephone. Sound travels faster through a string than through the air.
 

What is Light and Heat ?

What is Light and Heat ?

What is refraction ?
Light travels in straight lines. However, when it travels from one medium to another, for examples, from air to water, it bends. Bending of light at the boundary of the two media is known as refraction. It occurs because the speed of light changes as it enters a different medium.


How does a lens work ?
A lens is a carefully moulded piece of transparent material, such as glass or plastic, which refracts light to form an image.

When we look through a lens, we observed that the image of an object gets distorted. It's because light undergoes refraction as it travels from air to glass, and back to air again.

Lenses are usually used to magnify or reduce the size of the images of object. they are used :
Magnifying glasses
microscopes
spectacles
cameras
telescopes

Dispersion of light through a prism
We can prove this by shining white light through a prism. A prism is a transparent plastic or glass object, with smooth flat sides, that can refract light.

White light is refracted twice as it passes through a prism once, when it travels from air to the prism, and a second time when it travels from the prism to air. Light that comes out of the prism is no longer white, but it is broken up into the colours of rainbow. The breaking up of white light into its component colours is known as dispersion.

Dispersion occurs because of light of different colours travel at different speeds. Red light travels the fastest so, it refracts the least. Violet light travels the slowest so, it refracts the most. That is why red is always seen at one end of the rainbow, and violet at the other end.

Dispersion of light through water droplets

Water droplets in the air can act as tiny prisms. The droplets can be from the rain, the mist of a waterfall or a fine spray of water from a garden hose. It refract the sunlight the same way a prism does, and produce rainbows.

Transfer of heat
As light travels from one medium to another, heat also travels from one object or place to another. Heat travels from a region of higher temperatures to a region of lower temperature through conduction, convection and radiation.

Conduction
Heat can transfer transfer from one part to another within an object between objects.
An object is heated up, its particles collide with one another. Heat is transferred from the hotter region to the cooler region through these collisions of particles.

Conduction also occur between objects. Heat transferred when particles of both objects are touching each other.

Convection
Transfer of heat from one region to another by the movement of fluids is know as convection. 
A fluid is heated up, it expands. This means that its volume increases an its density decreases.
Hotter less dense fluid then rises and floats. Cooler, denser fluid flows to take its place. 

Radiation
Radiation release heat from the surface of most bodies that transferred  directly from one region to another.
Heat directly transferred without having to travel through any substance. Means that heat can be transferred without air.


.