• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

GCSE: Waves

Browse by
4 star+ (14)
3 star+ (21)
Word count:
fewer than 1000 (33)
1000-1999 (58)
2000-2999 (16)
3000+ (12)

Meet our team of inspirational teachers

find out about the team

Get help from 80+ teachers and hundreds of thousands of student written documents

  • Marked by Teachers essays 11
  • Peer Reviewed essays 13
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  1. Marked by a teacher

    Is Sunbathing Good?

    4 star(s)

    This produces certain chemicals called 'tryptamines' which improve our mood The sun can be bad for you because... There are also many reasons why the sun can be bad for you, e.g: * Exposure to solar and artificial UV radiation is widely recognized as a leading and preventable cause of skin cancer. * Exposure to high levels of sunlight, makes it four times more likely for you to develop cataracts in your eyes. * Sunburn can change the distribution and function of disease-fighting white blood cells and damage our DNA.

    • Word count: 2864
  2. Marked by a teacher

    refraction experiment

    4 star(s)

    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.

    • Word count: 1022
  3. Marked by a teacher

    Find the critical angle and refractive index for plastic using a graphical treatment for my results.

    4 star(s)

    Angle of incidence (I): Angle between incidence ray and normal at point of incidence. Point of incidence: Point at which incident ray meets boundary and becomes refracted ray. Critical angle: The particular angle of incidence of a ray hitting a less dense medium, which results in it being refracted at 900 to the normal. Normal: A line at right angles to boundary through chosen points. There are two main laws of refraction of light: 1. The refracted ray lies in the same plane as the incident ray and normal at the point of incidence.

    • Word count: 1127
  4. Marked by a teacher

    Investigation to find the change in the speed of light through perspex.

    4 star(s)

    a and refraction ? b and the refractive indices na and nb of the media are related through what has become known as Snell's Law: Snell's Law = the refractive index of the medium light is passing into the refractive index of the medium light is passing out of = Sin(i)/Sin(r). Apparatus Perspex block (semi-circular) Protractor sheet (A4) Lens Collimator Optical pins Power pack Method * First we gathered all the required equipment. * Then we set it up by placing the perspex d-block on the A4 protractor paper and plugged in the ray box into the mains.

    • Word count: 1374
  5. Marked by a teacher

    An investigation into the factors affecting the frequency of a standing wave

    4 star(s)

    I have decided to investigate the effect that altering the length of string along which the wave travels. From the above equations, I would expect the frequency to be inversely proportional to the length of string, as you would create a shorter wavelength when the string is shorter, and the speed can be kept constant. Because I am only investigating the change in frequency caused by a change in length of the string, both the tension and the mass per unit length of the strength need to be kept the same to get accurate results. Method To keep the Mass per unit length of wire the same, I am going to use the same piece of constantan wire for all my results, which has a mass per unit length of 32 (swp).

    • Word count: 1375
  6. Marked by a teacher

    Investigation:To find the refractive index of cooking oil.

    4 star(s)

    The greater the optical density, the greater the refraction index will be. In order to find the refractive index of cooking oil I will calculate the refractive index of other materials to give me an idea of what the answer might be. To ensure that the refractive index for cooking oil is as accurate as possible, ethanol and water will be tested during the pilot experiment. This should justify whether the method being used is correct because the results can be compared with the published values shown below. Substance Refractive index Air 1.00 Glass 1.50 Water 1.33 Ethanol 1.36 I therefore predict that the refractive index of cooking oil will be between the refractive index of water and glass.

    • Word count: 3078
  7. Marked by a teacher

    Are mobile phones dangerous? Research Project.

    3 star(s)

    Although mobile phones use radio waves, some can be classed as microwaves. Prolonged exposure to microwaves is known to cause "cataracts" in your eyes, which is a clouding of the lens, preventing you from seeing clearly. Recent research indicates that microwaves from mobile phones can affect parts of your brain - after all, you're holding the transmitter right by your head. Other research is inconclusive, although there is a feeling that you're more vulnerable if you're young and your brain is still growing due to having a softer skull. Results which suggest that mobiles might damage health are actually rare.

    • Word count: 2658
  8. Marked by a teacher

    Investigate how the angle of refraction is affected by different inputs of the angle of incidence through a glass block.

    3 star(s)

    In other words the angle of refraction is less than the angle of incidence. When light leaves a transparent material, it bends away from the normal. Snell's law The law of refraction relates the angle of incidence (angle between the incident ray and the normal) to the angle of refraction (angle between the refracted ray and the normal). This law, credited to Willebrord Snell, states that the ratio of the sine of the angle of incidence, i, to the sine of the angle of refraction, r, is equal to the ratio of the speed of light in the original medium, vi , to the speed of light in the refracting medium, vr , or sin i /sin r = vi / vr .

    • Word count: 891
  9. Marked by a teacher

    Resonance of a Wine Glass

    3 star(s)

    Energy is imparted to the glass molecules and causes them to resonate. The motion of your hand sets up a wave of vibration travelling through the glass. The vibrating glass causes air molecules to vibrate at the same frequency and this is the sound wave that you hear.1 Day 1 Aim Investigate how the volume of water in a wine glass affects the frequency it produces when resonated. * Stand * Selotape * Scissors * Measuring Cylinder Equipment * Wine Glass * Oscilloscope * Water * Sensitive Microphone Setting Up I plan to attach the microphone to the oscilloscope and position it closely to the rim of the wine glass.

    • Word count: 3756
  10. Marked by a teacher

    Experiment to Investigate which Factors Affect the Strength of an Electromagnet

    3 star(s)

    Variables The variables are the number of coils and the strength of the magnet. The number of coils I will change is in the independent variable and the strength of the magnet is the dependent variable. What I Intend to do I intend to investigate which factors affect the strength of an electromagnet. I intend to keep the voltage the same throughout the experiment I'm going to keep adding coils to the solanoid and find out how many paper clips it attracts. Apparatus Power Supply DC 0 - 13v demagnetising solanoid Connecting wires with plugs Crocodile clips Insulating wire (approximately 1m)

    • Word count: 560
  11. Peer reviewed

    Graphs illustrating variants of y = sin x.

    5 star(s)

    By doing this we are taking A<0. Graph 5 Graph 5 shows us that the wave flips around when A is negative. So we can conclude that when A<0 the wave will always be upside down From investigating graphs of y = Asin x, we can conclude that when the A is less than 1 then the wave compresses vertically and when A is greater than 1 the wave expands vertically. If A is less than 0, then the whole wave flips upside down.

    • Word count: 1010
  12. Peer reviewed

    What Is Fibre Optics

    5 star(s)

    This angle is called the angle of Total Reflection. Fibre Optics uses this simple principle for transmission. The core of the fibre optics cable, which is made of glass, has a higher index of refraction than the index of the cladding, which covers this core. So when light is injected into the glass core at the correct angle, it will reflect back from the surface and continue doing this in its forward direction of travel. In other words the light cannot "escape" from the fibre. COMPONENTS OF A FIBRE OPTICS SYSTEM The use of fibre optics is extensive, but the components used to make up a system are usually similar.

    • Word count: 1147
  13. Peer reviewed

    Optics - the human eye and coomon defects

    4 star(s)

    The amount of light entering the eye is controlled by the Iris. Sharp focusing is achieved by altering the shape of the lens. The shape of the lens is controlled by the ring of ciliary muscle which runs round the outside of the lens. (http://www.riverdeep.net/current/2002/01/012002_images/eye.jpg) Defects in the eye:- 1. Long Sight (Hypermetropia) In this condition we can see distant objects more clearly that ones that are nearby. This is usually because the cornea is not curved enough, which reduces the angle of refraction, and the lens cannot accommodate sufficiently to bring the diverging rays from near objects into sharp focus on the retina.

    • Word count: 651
  14. Peer reviewed

    Mobile Phone case study

    4 star(s)

    Macrocells are the largest type of base stations and provide the main coverage for mobile phone networks. Its antennas can be mounted on ground-based masts, rooftops or other structures and must be high enough to avoid obstruction. Macrocells provide radio coverage over different distances, depending on the frequency used, the number of calls being made and the surrounding environment. Microcells are used to improve capacity in areas where mobile phone communication is frequent, such as shopping centres. The antennas for microcells are mounted at street level. They are smaller than macrocell antennas and can usually be disguised, so that they are less obvious, in case of vandalism.

    • Word count: 1413
  15. Peer reviewed

    How does the number of coils on an electromagnet affect its strength?

    4 star(s)

    The more induced voltage, the stronger the electromagnet. An alternative way to strengthen an electromagnet is to replace the core with a "soft" iron core. Prediction: - An increase in the number of coils applied to the iron nail will cause an increase in the number of paperclips being picked up. (a positive correlation between the two variables) This prediction derived from the scientific knowledge above - 'Therefore, the more turns of the coil you have, the greater the magnetic field and the stronger the electromagnet.' Apparatus: - Iron nail (1)

    • Word count: 1038
  16. Peer reviewed

    Physics of water waves.

    4 star(s)

    After reflection the wave has the same speed, frequency and wavelength as it did prior to the collision. This is similar to the reflection of circular waves off a straight barrier. The reflected waves are also circular, however they have a centre point that is position behind the barrier. This point is known as the "image" of the source. Reflection of a parabolic or concave barrier can be closely compared to that of light waves off a concave mirror. If the incident wave was straight, the reflected waves are curved, and they converge at a fixed focal point.

    • Word count: 603
  17. Peer reviewed

    Experiment to investigate the relationship between speed and depth for a water wave.

    4 star(s)

    For my preliminary work, I did the experiment and tested that a wave would be able to be created. The preliminary work brought up the problem of how high the wooden block should be held up before it is swung into the water, it was decided that it should be swung from about 4cm above the bottom of the guttering. Safety Precautions: Even though safety is a virtue the experiment being conducted is a relatively safe one. The only major danger is slipping on the water, which has been spilled, and so when water is spilled the water is cleaned up immediately.

    • Word count: 1006
  18. Peer reviewed

    The Electromagnetic Spectrum.

    3 star(s)

    Microwaves Microwaves have frequencies between 1010 and 1011 Hz, and have a wavelength of 10-2 to 10-3 , they are produced by microwaves, ovens and microwave transmitters and are detected by microwave receivers. We use them in cooking foods, communication and radar so when you use a microwave you're using microwaves or when you're using a mobile phone you're using microwaves. Infrared Infrared covers waves with wavelengths between 1mm to 50 nm and frequencies from 300GHz to 400 THz; however it can be split into three different parts: * Far - Infrared Wavelength: 1 mm -10 �m Frequencies: 300 GHz

    • Word count: 730
  19. Free essay

    Do mobile phones adversly affect our health? - Case study

    3 star(s)

    Radio waves are the second weakest type of wave, so would not create much of a risk to the human body, albeit affect the tissue slightly. There is a diagram of the electromagnetic spectrum on the next page. "Mobile phones connect to the base station providing the best signal - usually the nearest. As a person moves away from the base station the signal becomes weaker, so the mobile phone automatically adjusts its own RF field strength to maintain the minimum level needed to communicate with the base station."

    • Word count: 1143
  20. Peer reviewed

    What causes feedback in a guitar or microphone?

    3 star(s)

    Let's deal first with the simple case of a microphone and an amplified speaker. (See the figure, but ignore the guitar for now.) Feedback occurs when a "loop" between an input and output is closed. In this scenario, the microphone serves as the input and the amplified speaker provides the output. In our example, the loop between the input and output closes when the sound radiated from the amplified speaker reaches the microphone and is subsequently amplified again. In effect, the cat is chasing its tail. (See the dashed red line connecting the loudspeaker to the microphone through acoustic feedback in the figure.)

    • Word count: 586
  21. Peer reviewed

    The Fundamentals of Radio Wave Propagation

    The answer, in three words, is radio wave propagation. Radio wave propagation theory is of particular importance to wireless communications, for, without a preliminary understanding of the physical nature of wave propagation it is impossible to ensure that communications can be established at all. * Transmission and Reception In a wireless environment radio frequencies are transmitted outward from a source, which is usually an antenna.

    • Word count: 288
  22. Peer reviewed
  23. Insulation Materials Experiment Method We put 100ml of water at 80C into each of 6 beakers. Each beaker had a different material wrapped around it, and we measured the amount of time taken for the temperature of the water to decrease by 10C to 70C

    Results Time taken for each attempt (seconds) Material 1 2 3 Average time (seconds) Polystyrene 179 192 201 190.67 Carpet 201 190 191 194 Bubblewrap 190 225 194 203 Fibreglass 213 178 198 196.33 Tissue paper 172 169 225 188.67 Cotton 162 176 - 169 Conclusion From our results wee can conclude that bubblewrap is the best insulator tested. It took an average of 203 seconds to lose enough heat energy to the atmosphere to reduce the temperature of the water to 70�C.

    • Word count: 393
  24. Focal length of Concave and Convex lens

    With mathematical simplification, the Lensmaker's equation can be applied as follow . Procedure Type A is a convex lens with shorter diameter B is a convex lens with longer diameter METHOD I, We put the lens in front of the window and then try to obtain a sharp image on the screen. When we get a sharp image, then measure the distance between the screen and the lens and name it as F. The distance, F, is the focal length of the lens. Method II First, put a light source with a transparent object F in front of a convex lens.

    • Word count: 786
  25. refractive index prac report

    Materials: Geoliner or Protractor, Power Pack Light Kit & accessories, White paper Method: Analysis Angle of Incidence Refracted Angle 5 4 10 6 15 8.5 20 10 25 13 30 16 35 19 40 22 45 26 50 27.5 55 29.5 60 33.5 65 35.5 70 36.5 75 37 80 37.5 85 38 It can be seen that from the table, the light ray is bent towards the normal because the angle of incidence is greater than the refracted angle thus stating that the Perspex block is of a greater density than air.

    • Word count: 699

Marked by a teacher

This document has been marked by one of our great teachers. You can read the full teachers notes when you download the document.

Peer reviewed

This document has been reviewed by one of our specialist student essay reviewing squad. Read the full review on the document page.

Peer reviewed

This document has been reviewed by one of our specialist student document reviewing squad. Read the full review under the document preview on this page.