Investigating into How the Depth of Water has an Affect on the Speed of the Wave
Investigating into How the Depth of Water has an Affect on the Speed of the Wave Aim The aim of this experiment is to investigate the relationship between the depth of water and the speed of the wave in it. By studying the speed of a single wave in the water as it travels along a tray it is possible to find how the depth of the water affects the speed of the wave. I will generate the pulse in the tray of water by dropping the tray from a height of 5cm. Background Knowledge A wave is a continuous movement of individual particles to form a way of transportation of water, light, sound and others such as paraphernalia. There are two different types of waves shown below. Transverse waves are waves that cause a crosswise disturbance of the medium through which they travel. Longitudinal waves are waves that have vibrations travelling in the same direction as the wave itself. In my experiment I will be studying transverse waves. The speed of the wave may be calculated by timing the motion of the wave from one end of the tray to the other. A measurement of how far the wave travelled as it move backwards and forwards will be needed. I will use the following equation to work out the speed of the wave: Hypothesis I predict that the greater the depth of water, the faster the waves will travel. The reason for this is that when the water is shallow, the container bottom begins
Is the speed of sound affected when it travels threw different temperatures of air
G.Bourne Is the speed of sound affected when it travels threw 18/12/01 different temperatures of air Background knowledge The speed of propagation of sound in dry air at a temperature of 0° C is 331.6 m/sec. If the temperature is increased, the speed of sound increases; thus, at 20° C, the velocity of sound is 344 m/sec. Changes in pressure at controlled density have virtually no effect on the speed of sound. The velocity of sound in many other gases depends only on their density. If the molecules are heavy, they move less readily, and sound progresses through such a medium more slowly. Thus, sound travels slightly faster in moist air than in dry air, because moist air contains a greater number of lighter molecules. The velocity of sound in most gases depends also on one other factor, the specific heat, which affects the propagation of sound waves. When a tuning fork is held over a tube, a standing wave pattern is formed in the tube. Under the right conditions constructive interference will occur at the opening to cause resonance. This is a very noticeable rise in the amplitude, or loudness, of the sound that is caused by the addition of two waves in phase with each other. One of the waves is traveling down the tube and the other is traveling back up the tube. In a closed end tube, like the
Deviation of Light by a Prism.
Deviation of Light by a Prism Aim The aim of this investigation is to test using a prism how the angle of deviation (how far the light ray is deviated from its original position) is affected by varying the angle of incidence (where the light ray goes into the prism), and whether this has any relation to the angle of emergence (where the light actually comes out of the prism). Planning I firstly need to conduct theoretical work and a preliminary investigation to test what is going on and to get a clearer view of the aspects of the investigation. In my theoretical work I will have to use the geometry of triangles and Snells Law. For Snells law to work, I will need to know the refractive index of the glass that I am using. To do this I will use a glass block of the same glass as the prism, and then use sighting pins (and light) to pinpoint the incident ray and the emergence ray and then find the angle of refraction. A more detailed description of how this experiment is going to work can be seen below. To find the refractive index of the glass that I will be using in the actual experiment, I set up a glass block that was of the same type of glass as the prism, and lined up sighting pins through it. This enables me to draw the angle of incidence (measured from the Normal (dotted line below), a line at 90° to where the incident ray strikes the glass block) and this also
An Experiment to Measure the Speed of Light in Glass.
An Experiment to Measure the Speed of Light in Glass Plan Method Apparatus - Glass D-Block Optical pins Cork board Protractor printed on paper To find the refractive index you must first find the angle of incidence and reflection. You use the method of no parallax, I will use ray tracing with the method of no parallax. This involves placing the D-Block on the protractor paper, so the normal is at 0o, the center of the D-Block. I will place two optical pins pointing at the normal, lining up the two pins, I will place the third lined up with these two, looking through the D-Block. I will measure the angle between the normal and the line that connects the optical pins in front of the D-Block to the D-Blocks front center (i), and the angle between the normal and the line that connects the optical pin behind the D-Block to the D-Blocks front center (r) and record them. To be safe I will make sure I am careful with the apparatus. Theory I know that when light goes through a different medium from which it is already in (a vacuum for example) it slows down, this is caused by there being more particles in the way. Light refracts because the change in speed, hitting the medium at an angle, causes one side of the ray to slow down first, and so it turns, towards the normal. The normal is a line at right angles to the medium. If a ray went down the normal, no refraction would
Strength of an Electromagnet
Strength of an Electromagnet Aim and Plan Aim To find out the strength of an electromagnet by changing the number of coils of wire wrapped around it. Prediction I predict that as I increase the number of coils around the electromagnet, the electromagnet will be able to lift increasing amount of weight. I predict that when I have plotted out my results into a graph I will have a straight line, meaning that the weight lifted is directly proportional to the number of coils around the electromagnet. Plan First of all you will need to set up all the apparatus highlighted in blue on page 2. A diagram of how this should be set up is shown below. Now that all the apparatus is correctly set up turn on the power pack and make sure that it is set to 3 volts. Then start with 2 wraps of coil and work your way to 20 from there. Start by slowly adding 100g weights but after that add 10g weights. When the electromagnet can not hold any more the weights will fall and you will have to count up all the weights bar the one that caused the fall and record the weight at the end. Do each experiment at each number of coils three times in total. Then make an average of your results. Variables Kept constant: Current from the power pack Space between each coil. The type of Electromagnet, iron core Variable: The number of coils To measure: The mass in grams picked up by the
Physics Case Study - Do Sunbeds Cause Skin Cancer?
Contents Title Page - Pg 1 Contents - Page 2 Introduction - Pg 3 The Structure of the Skin - Pg 4 The Electromagnetic Spectrum - Pg 6 How Skin Tans - Pg 7 Skin Cancer - Pg 8 Causes of Skin Cancer - Pg 9 Conclusion - Pg 11 Bibliography - Pg 13 Introduction As the pressure on young people to become perfectly preened and tanned steadily increases, more and more turn to sunbeds as a way to find that perfect summer glow. However, the darker side to the story, the soaring numbers of skin cancer, are they paying for their vanity, or is it pure coincidence. The title I have chosen to study is "Do Sunbeds Cause Cancer?". Why? - Because in my opinion it is a currently pressing issue, so many young people today are turning to sunbeds, and with the sunbeds themselves becoming stronger and stronger, are we killing ourselves? I'm looking for evidence to help me come to a personal conclusion. This will include articles either supporting sunbeds as a cause for skin cancer, with evidence from studies showing some undeniable correlation. Alternatively, I am also looking for evidence suggesting other causes, providing an alternative conclusion. I hope by the end of this case study, I will have a better understanding of the effects of UVA/B radiation on the skin, and that I will be able to make a decision, as to what I think. The Structure of the Skin Many people actually know
refraction experiment
REFRACTION EXPERIMENT Aim: To study the phenomenon of refraction of light by using a glass block. Theory: Light is one of the most fundamental energy forms and an understanding of several of its properties is essential to any understanding of science. In this investigation we would be seeing the different phenomenon of refraction of light. Refraction is a change in the direction of radiation that occurs when it crosses the interface between two media in which the radiation travels with different speeds. The radiation undergoes a change in speed, in wavelength, and in direction. These are a few common terms in relation to refraction of light: > Reflection: the process by which radiation that strikes a surface separating two media of different densities is in part or in whole turned back into the medium from which it originated. The radiation rebounds from a barrier in its path without a change in speed. > Normal line: A line perpendicular to the surface at the point where a ray of light strikes. > Incident Ray: A ray which impinges upon a surface. > Refracted Ray: a ray that has changed direction after crossing from one media to another, in which the speed is different. > Emergent ray: the light ray leaving a medium in contrast to the entering or incident ray. > Angle of incidence: the angle between the incident ray and a normal. > Angle of refraction: the angle
What factors affect the strength of an electromagnet?
What factors affect the strength of an electromagnet? Introduction I will be testing the factors which will make an electromagnet stronger. Electromagnets are magnets which are created and are easily controlled by electricity. All magnets have a region of space around them called the magnetic field which exerts a force on any magnetic material such as iron and steel or any other magnet which enters it. This force can be attractive and repulsive. If an electric current flows through a coil of wire a magnetic field is formed around the coil creating an electromagnet. This is a magnet which can be switched on and off. To carry out this investigation I will follow the following steps: Insulated copper wire was coiled around a metal nail to make turns and then inserted into a power supply box. The coiled nail was put over a sheet of paper which had iron filings on, 6v was used and when the power was switched on the wire appeared to pick up the iron filings and this told us that an electromagnet was formed, because it was a short circuit the power supply switch of by itself and we had to reset it. As I stated before that the force can be attractive or repulsive in this case the force was attracted. For our investigation we didn't use iron filings but we used a soft iron which was the nail, and the wire was wrapped around the core of the soft iron. We used
Energy sources
Type of energy Where it is from Advantages Disadvantages Solar Energy from sunlight is captured in solar panels and converted into electricity Potentially infinite energy supply. Single dwellings can have own electricity supply Manufacture and implementation of solar panels can be costly. Wind Wind turbines (modern windmills) turn wind energy into electricity. Can be found singularly, but usually many together in wind farms. Potentially infinite energy supply. Manufacture and implementation of wind farms can be costly. Some local people object to on-shore wind farms, arguing that it spoils countryside. Tidal The movement of sea water in and out drives turbines. A tidal barrage (a kind of dam) is built across estuaries, forcing water through gaps. In future underwater turbines may be possible out at sea and without dam. Should be ideal for an island country such as the UK. Potential to generate a lot of energy this way. Tidal barrage can double as bridge, and help prevent flooding. Construction of barrage is very costly. Only a few estuaries are suitable. Opposed by some environmental groups as having a negative impact on wildlife. May reduce tidal flow and impede flow of sewage out to sea. Wave The movement of sea water in and out of a cavity on the shore compresses trapped air, driving a turbine. Should be ideal for an island country. These are more
Find the refractive index of a plastic block.
Name Jonathan Tam Class: 13A Yew Chung International School Physics Aim: Find the refractive index of a plastic block Method: I will use two methods to find the refractive index of plastic. The first one is to use the critical angle, and the other one is to use Snell's Law. Critical Angle method: . Set up the apparatus as shown. Put a piece of white paper under the apparatus. Turn off lights from the surroundings. 2. Put a black slid into the light box so that only a thin ray will be shone. 3. Turn on the light box. Adjust the angle of incidence so that there are no refracted rays. Once the refracted ray disappears, the angle of incidence is the critical angle. You should start seeing a reflected ray coming out of the plastic block as shown above. 4. Plot points on the paper to show the light rays. Connect the points to form lines. 5. Draw normal on the paper between the incident ray and reflected ray as shown. Measure angle i (angle of incidence, critical angle) 6. Repeat step 3 to 5 at least 3 times to get sufficient results. Snell's Law method: . Set up the apparatus as shown. Put a piece of white paper under the apparatus. Turn off lights from the surroundings. 2. Put a black slid into the light box so that only a thin ray will be shone. 3. Turn on the light box. Plot points on the paper to show the light rays. Connect the points to form lines. 4. Draw
