CSEC Physics Syllabus - Effective for examinations from May - June 2015
Section A - Mechanics
Energy
Forms of Energy
Specific Objective 5.1
define energy;
Specific Objective 5.2
identify the various forms of energy;
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Energy
Is defined as the ability to do work. Where work done by a force is given by the magnitude of the force multiplied by the distance moved in the direction of the force.
Work Done = Force × Distance moved in the direction of the Force
W = F × d
The S.I. Unit of Work is called the Joule (J).
Forms of Energy
Gravitational Potential Energy
This type of energy is stored by an object which is a certain height above a reference point; in most cases the ground.
Gravitational Potential Energy = Mass of object × gravity × Height
G.P.E. = m × g × h
Examples
Gravitational Potential Energy is stored in:
1. water at the top of a waterfall and/or in a high-level reservoir,
2. in the heavy driving weight of a wound-up grandfather clock and
3. A cyclist has gravitational potential energy when he reaches the top of a hill.
Elastic Potential Energy
Objects that are elastic will store energy when they are stretched, twisted, or bent.
Examples
Elastic Potential Energy is stored in:
1. the stretched elastic of a catapult,
2. the wound-up spring of a clockwork motor and
3. the bent condition of a diving board when a diver is about to jump from the end.
Chemical Energy
This form of energy is stored in the bonds of chemical compounds.
Examples
Chemical Energy is stored in:
1. food in all its variety,
2. fossil fuels such as coal, oil, gas and
3. the car battery.
Electrical Energy
This energy is caused by the movement of electrons along a conductor. Electrical Potential Energy is energy stored in charged particles within an electrical field.
Examples
Electrical Energy is experienced when:
1. a battery is used,
2. a power station generator spins and cuts magnetic lines of flux and
3. a lightning strikes.
Magnetic Energy
This is the work done on a magnetic object when placed in a magnetic field. This work could either be classified as attraction or repulsion.
Examples
1. Refrigerator magnets - to seal and close the refrigerator doors,
2. Motors - automotive, lawnmower, kitchen mixer, washing machine and
3. Recording media - VCR, audio & video cassettes, hard and floppy disks, magneto-optic disks.
Thermal Energy
This energy is a measure of the amount of heat or kinetic energy of the particles contained in a specific space.
Examples
1. The heat produced by sunlight,
2. Baking in an oven or cooking over a stovetop flame and
3. A by-product of exothermic reactions and the use of Electrical Energy.
Nuclear Energy
The energy released during nuclear fission or fusion.
Examples
1. Nuclear fission heat is used to generate electricity,
2. Cobolt-60 is used by hospitals to sanitize equipment such as catheters, scalpels, and
3. In medical radiotherapy for cancer treatment and in medical imaging.
Kinetic Energy
This is the energy of moving objects.
Kinetic Energy = 1/2 × Mass of object × Velocity2
K.E. = 1/2 × m × v2
Examples
1. A fast-moving car has a large amount of kinetic energy,
2. a cricket ball leaving the bowlers hand and bowled towards the batsman and
3. Walking and/or running.
Sound Energy
A longitudinal wave motion passes sound energy from molecule to molecule in the form of mechanical vibration with a particular frequency and amplitude.
Examples
1. A buzzing bee,
2. Music played from an instrument or speaker and
3. An airplane taking off.
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