JAMB Registration & Requirements 2017/2018 (20 December 2016 – 9 February 2017)

JAMB Registration & Requirements 2017/2018 (20 December 2016 – 9 February 2017) JAMB Registration form for 2017/2018 Computer Based Test (CBT) is out online at jamb.org.ng. The guidelines, requirements...

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JAMB Guidelines & Requirements 2017/2018 For Computer Based Test (CBT) Centre

  JAMB Guidelines & Requirements For 2017/2018 For Computer Based Test (CBT) Centre The Joint Admissions and Matriculation Board (JAMB) has released new guidelines that would help to...

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Analysing Electromagnetic Waves

1. Electromagnetic waves consist of vibration of magnetic field and electric field which are perpendicular to each other. 2. Therefore, Electromagnetic waves are transverse waves. 3. The velocity...

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Electromagnetic Spectrum

When you watch television, listen to the radio or cook something in a microwave oven , you are actually apply the properties of electromagnetic waves. Do you know what is an electromagnetic wave? Electromagnetic waves are propagating waves that travel in space with both electric and magnetic components. These components oscillate at right angles to each other and to the direction...

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Analysing Sound Waves

1. Sounds are mechanical waves. They are caused by vibrating objects. Hence, all vibrating objects produce sound. As an example: The strings of a guitar, the skin of a drum and a tuning fork vibrate...

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Speed of Sound, Loudness and Amplitude of Sound

Speed of Sound 1. The speed of sound,v, in a medium can be defined as v = fλ, where λ is the wavelength and f is the frequency. The SI units of v is ms-1, f is Hz and λ is  m (metre). 2....

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Damping and Resonance of Waves

Displacement –time and Displacement –distance graphs. Wave motion occurs because of the vibration of particles from their resting position. We can show the displacement of particle (from its rest...

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Analysing Interference of Waves

Principle of Superposition 1. The principle of superposition states that at any instant or moment, the wave displacement of the combined motion of any number of interacting waves at a point is the...

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Analysing Diffraction of Waves

1. Diffraction of waves is a phenomenon in which waves spread out as they pass through an aperture or round a small obstacle. 2. The effect of diffraction is obvious only if a) the size of the...

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Analysing Refraction of Waves

Any type of wave can be refracted, refracted is a change in direction. Refraction occurs when the speed of a wave changes, as it moves from one medium to another. Refraction of Plane Water Waves 1....

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Meaning And Definition Of Waves

WavesUnderstanding WavesWave and Energy A Wave is a disturbance that transfers energy between 2 points through vibrations (or oscillations) in a medium, without transferring matter between the two points. Example 1: When you hold the end of a rope and a friend of yours wave the rope at the other end up and down, then a wavy movement appears. This is a movement of the rope and it...

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Reflection of Light on a Curved Surface: Method to draw ray diagrams

1. There are two main types of curved mirrors, namely: (a) Convex Mirror (b) Concave Mirror 2. On a Concave mirror, the rays that are parallel and close to the main axis (small opening) converge...

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Relationship between Critical angle and Refractive Index and Application of Total Internal Reflection

Let’s say that the less dense medium is air (n=1). Then the refractive index of the second medium is: n = sin i /sin r    = sin 90° / sin c n =  1 / sin c So, REFRACTIVE...

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Understanding Total Internal Reflection of Light

1. If the angle of incidence is allowed to exceed the critical angle, it is found that light rays are not refracted. This is because all of the light rays are reflected back. 2.This phenomenon is...

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Analysing Reflection of Waves

1. Reflection of waves occur when a wave strikes an obstacle. The wave undergoes a change in the direction of propagation or transmission when it is reflected. 2. The incident wave is the wave before...

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Refraction of Light

Why do you think that part of a spoon that is immersed in water looks bent? Many people think that as a stick/solid is put in liquid it becomes bent. Do you think the same? The reason why the...

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Understanding the Reflection of Light: Law of Reflection of Light

1. The reflection of light can be studied by using light ray(s) and a plane of mirror which is placed on a piece of white paper. 2. When the ray of light is incident onto the surface of a plane...

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Uses of Gas Laws

1.Bicycle Pump When the piston is pushed into the cylinder, the air in the cylinder is compressed. According to Boyle's Law, the air pressure inside the cylinder will increase. This causes the air pressure in the cylinder to become higher than the pressure inside the tyre. Therefore, the air can flow into the tyre. 2. Hot-air balloon When the air in a balloon is heated at atmospheric...

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Pressure Law

The Pressure Law can be clarified using the Kinetic Theory of Gases. When gas is heated at a fixed volume, the gas molecules will move faster and with more energy. The rate of collision of the gas molecules onto a unit area of the wall of the container will increase. Each collision will also produce a greater force, because the change in momentum for each molecule increases when its...

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Boyle's Law

Boyle's Law can be explained by using the kinetic theory of gases. When the volume of a gas in a container of gas molecules is reduced. a) its density increased, that is, the number of gas molecules...

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Charles' Law

Charles' Law can be explained by the kinetic theory of gases.When the temperature of a gas is raised, the gas molecules will move more actively and with more energy.The rate of collision of the gas molecules onto a unit area of the wall of the container will increase.Each collision will also produce a greater force because the change in momentum for each molecule increases when its speed...

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Absolute zero temperature and the absolute zero scale

The absolute zero temperature of - 273 °C is the lowest possible temperature that could be attained. The volume of the gas becomes zero at the absolute zero temperature but before this temperature is attained, all of the gas would have changed to liquid. The Kelvin Scale is also known as the absolute zero temperature scale. The SI Unit is Kelvin (K) The temperature interval...

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Universal Gas Law

From the various Gas Laws, the relationship among the three quantities; Volume, V, Temperature, T and Pressure, P can be connected by the equation as follows:Boyle's Law : PV = a constant with T fixedCharles' Law: V/T =  a constant with P fixedPressure Law: P/T = a constant with V fixedAll three Gas Laws are connected to obtain a Universal Gas Law which is given by PV/T = a constant.That...

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Understanding the Gas Laws: Gas Laws and Kinetic Theory of Gases

Gas theory can be explained by way of the kinetic energy. When gas molecules hit the walls of the container and bounce back, a change in momentum occurs in a split second. This is obviously a very very fast action. The end result of the above momentum is that the walls of the container experience a force. Pressure is defined as the force that acts on a unit surface area. Therefore,...

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Application of Specific Latent Heat

Steaming FoodThe specific latent heat of vaporisation for water is large.Plates filled with food are able to absorb heat from the hot steam.The condensation of steam at the base of the plate releases a large quantity of heat and thus enables food such as cakes,fish, eggs and others to be steamed.Cooling drinks with cold water and iceA glass of hot water can be cooled faster by adding...

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Specific Latent Heat of Vaporisation

The specific latent heat of vaporisation, L of a substance is the heat quantity required to convert one unit mass of a liquid into water vapour at its boiling limit without any change in temperature.Its unit is JKg-1.If m Kg of liquid or water vapour is involved, the quantity of heat, Q absorbed or released isQ = mlQ = quantity of heat that is absorbed or released.m = mass of the substancel...

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Specific Latent Heat 2

The specific latent heat of a substance is the energy which is required to change 1 Kg of a substance from a certain physical condition to another physical condition without any change in temperature. The...

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Understanding Specific Latent Heat I : Latent Heat

Before we begin, let's think about this situation. When ice melts. There is a change of phase from solid to liquid. The ice absorbs heat from the surroundings. The heat energy absorbed by the ice does not cause the increase in temperature. The energy absorbed is not transferred to the molecules of ice as kinetic energy. 1. When a substance experiences a change of phase, it absorbs...

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Application of Specific Heat capacity

As we have read (supposedly) about the concept of heat capacity and specific heat capacity, we will discuss briefly about the application of Specific Heat capacity in daily situations. 1. Substances having a small specific heat capacity can be quickly heated up, it also experience a big change in temperature even though only small amount of heat is supplied. 2. Substances having...

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Understanding Specific Heat Capacity: idea of Specific Heat Capacity

Understanding Specific Heat Capacity Heat Capacity 1. The heat capacity,C , of a substance is the heat which is required to increase the temperature of the substance by 1°C. 2. The unit for heat capacity is J° / C. 3. For example, the heat capacity for 100 g of water is 420 J°/ C. This means that 420 J of heat energy is required to raise the temperature of 100 g water by 1°C. To...

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Thermometers and calibration of Thermometers

The definition of temperature as a physical quantity is based on the principle of thermal equilibrium.Let say there are Thermometer A, Liquid B and Liquid C.We put thermometer A into liquid B and then after thermal equilibrium is achieved we record the value.We put thermometer A again into liquid C and after thermal equilibrium is achieved we record the value of reading in the...

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