Galileo developed the concept of inertia.'; var tip54 = '
SI units for mass are kilograms. Mass is a scalar quantitiy which does depend on gravity - the mass of an object is 60 kg on the Earth, on the Moon, on any planet. Mass and weight are different.
Is a scalar quantity. It is the product of an applied force and the displacement of an object in the direction of the applied force. The unit for work is a newton.meter (N.m) which equals a Joule (J).
Is done when the applied force and the displacement act in the same direction.
Is done when the applied force and the displacement act in opposite directions.
Is the ability to do work. When work is done, energy is transferred from one object to another. The unit for energy is the Joule.
)A push or a pull that is applied to an object. The unit for force is the Newton (N). It is a vector quantity and therefore requires direction.
Is the rate at which work is done. It is a scalar quantity with SI units of watts (W). Another commonly used unit is the horsepower.
Since work done is approximately equal to the energy used, W = ~E, power can also be described as the rate at which energy is used. 
One horsepower is equal to 746 joules/second (746 W). The unit horsepower was used to describe the output of a workhorse.
Is the energy of motion. It can be calculated by
where:
Ek = kinetic energy (J)
m = mass (kg)
v = velocity or speed (m/s)
energy of rest.
Is one in which there is no change in kinetic energy after the collision has occurred. Kinetic energy is conserved.
Is one where some energy is "lost" when colliding objects are in contact. This "lost" or dissipated energy usually results in the production of heat. It may also produce sound, light, or other forms of energy.
Is the energy stored as a result of the vertical position (height) of an object. It\'s position may be relative to the ground level or a base level. It may be calculated using
Eg = mgh
where Eg = gravitational potential energy (J)
m = mass of the object (kg)
g = 9.80 m/s2h = change in height relative to the reference point (m)
Is an arbitrary reference point from an object\'s vertical position may be calculated. This change in height relative to the reference point may then be used to calculate gravitational potential energy.
Is the surface of the earth or the floor of any room from an object\'s vertical position may be calculated. This change in height relative to the reference point may then be used to calculate gravitational potential energy.
Is the sum of the kinetic and gravitational potential energy in an object. ET = Eg + Ek
is the rate of flow of charge passing through a cross-sectional area in a conductor. It is considered to be a flow of positive charge.
is the magnitude of the charge on a single proton or electron. The symbol for elementary charge is e. E = 1.602 x 10,-19 C where C = 1 coulomb.
state that: Opposite electric charges attract each other. Similar electric charges repel each other. Charged objects attract some neutral objects.
is the rate of flow of charge passing through a cross-sectional area in a conductor. It is considered to be a flow of positive charge.
At any junction in an electric circuit, the total current flowing into the junction is the same as the total current leaving the junction.
The algebraic sum of the potential difference around any closed path or loop must be zero.
In this circuit, electrons can flow along one path only.
In this circuit, electrons can flow along one or more pathways (i.e. alternate paths for current to follow).
This resistance can be considered to consist of a single resistance, which replaces two or more resistances.
Is the rate at which work is done. It is a scalar quantity with SI units of watts (W). Another commonly used unit is the horsepower.
Since work done is approximately equal to the energy used, W = ~E, power can also be described as the rate at which energy is used. 
Born: 12 March 1824 in Königsberg, Prussia (now Kaliningrad, Russia)
Died: 17 Oct 1887 in Berlin, Germany
Kirchhoffs laws, which he announced in 1845, allowed calculation of currents, voltages and resistances in electrical circuits with multiple loops, extending the work of Ohm. Kirchhoff considered an electrical network consisting of circuits joined at nodes of the network and gave laws which reduce the calculation of the currents in each loop to the solution of algebraic equations.
Resistance is anything that causes an opposition to the flow of electricity in a circuit. It is used to control the amount of voltage and/or amperage in a circuit. Everything in the circuit causes a resistance (even wire). It is measured in OHMS (
).Power can be defined as the rate at which energy is used. The unit for power is the watt.
The electric potential difference (V) is the work done per unit charge as a charge is moved between two points in an electric field.
A chasis ground or a ground may be a common plane of zero voltage compared with the rest of the circuit.
An electric field is a region in space where a force is exerted on a positive test charge.
Electric lines of force represent the direction that a positive test charge would move in an electric field. By convention, they originate at positively charged objects and terminate at negatively charged objects.
electric potential or potential difference expressed in volts. Also known as electromotive force - it is the force that pushes and pulls electrons through a conductor.
the longitudinal electrical resistance of a uniform rod of unit length and unit cross-sectional area : the reciprocal of conductivity. Resistance depends on the resistivity of the material. The resistivity is defined as the resistance of a cylinder of the material 1 metre long with a cross-sectional area of 1 m2. Resistivity varies with temperature. It is measured in ohms m2/m. (Some texts use ohm m.)
a complete disappearance of electrical resistance in a substance especially at very low temperatures.
Is the spontaneous breakdown of an atom and results in the emission of particles or electromagnetic radiation.
Are elements that have the same atomic number but different atomic masses due to a change in its number of neutrons.
Are positively charged particles emitted from alpha decay. These particles are helium nuclei
Are electrons that are emitted from beta decay. For an electron, the subscript represents the charge and not, as in most cases, the number of protons.
Are usually emitted along with alpha and beta decay. Gamma rays are electromagnetic radiation ( a form of light) that produces no change in the atomic mass or atomic number of the radioactive nucleus. The symbol used for gamma rays is
.Is the measurement of radiation and the study of its effects on living organisms.
Describes how much energy is deposited by a source per kilogram of exposed tissue. Its SI unit is the gray (Gy) and a common non-SI unit is Rads.
1 Gy = 1 J/kg = 100 Rads
The radiation for the treatment of cancer generally involves an absorbed dose of 40 Gy.
Measures the biological damage produced on an organism. Its SI unit is the sievert (Sv). Dose equivalent (Sv) = absorbed dose (Gy) quality factor (Q).
A number assigned to each type of radiation to describe its biological effects. It was defined by comparing its effects with those of a standard radiation of 200 keV X-rays. Quality factors are approximate since they depend on the energy of the radiation and the type of tissue being irradiated. Note: a keV is a kiloelectronvolt
Measures the activity of a source. One becquerel is equal to one emission per second.
1 Bq = 1 emission per second = 1 Curie (Ci)
Results when a slow moving neutron is absorbed by a heavy nucleus causing it to split into smaller nuclei.
Is a substance that is used to slow down the neutrons in nuclear reactors. Some common moderators are: graphite, heavy water, and beryllium. In the CANDU reactor the moderator used is heavy water, D20. It contains deuterium
, which is an isotope of hydrogen.Is the difference between the masses of the parent atom and the slow moving neutron and the masses of the daughter atoms with the emitted neutrons. It can be used to determine the energy released during fission.
where E = energy released
c = speed of light =
m= nuclear mass defect
A nuclear reaction where the neutrons produced during a reaction causes a chain of similar reactions. A controlled chain reaction occurs in a nuclear reactor whereas in an atomic bomb an uncontrolled chain reaction occurs.
The process of increasing the percentage of uranium-235 in a natural uranium ore so that a chain reaction will be sustained.
Are used to control the rate of a chain reaction by capturing neutrons. They are often made of boron or cadmium and are inserted into the moderator and fuel to reduce the rate of fission.
It is a device where a controlled chain reaction occurs. The energy released from this reaction is used to drive turbines, which generate electricity.
Is the minimum mass of fissionable material that will produce a nuclear explosion. If the amount of U-235 is to small, the neutrons produced during fission will be less than the number of neutrons that will escape from the surface of the mass.( i.e. no sustained chain reaction)
- Open pit mining is common in Canada.
- The disposal of tailings is a concern. Tailings are the waste material after the uranium compound has been removed. They are radioactive and are often dumped in nearby "ponds".
- Miners have a higher degree of stomach cancer than most Canadians.
- Refueling can be done without shutting down the reactor. The fuel bundles can be removed from the pressure tubes and replaced with new bundles.
- The moderator can be easily drained from the reaction vessel, thereby stopping the chain reaction.
- If there is a problem with the coolant, water from elevated tanks automatically enter the calandria.
- The control rods are attached to electromagnets that will drop them into the calandria if there is a power failure.
In a nuclear accident reactors do not explode like a bomb (since the critical mass of the fuel is not present) they go through a process called a meltdown. A meltdown results when the reactor loses its coolant. The temperature raises unit the reactor melts (control rods melt, steel walls of calandria melt, etc.).
The Atomic Energy of Canada Limited designed the CANDU reactor. It is a federal crown corporation which leads in the development and marketing of the reactor.
Change the steam back into water so that it can be recycled.
The coolant used in this system is also heavy water. It flows through the pressure tubes in the calandria and transfers the heat from the fuel to ordinary water through a heat exchanger. This ordinary water produces steam, which will turn turbines to generate electricity.
This is another word for Reactor Vessel. It contains the pressure tubes and the moderator.
Natural Uranium Ore --» (Refined) --»Uranium Oxide pellets --» (stacked into) --»Cylindrical Rods --» (arranged into) --»Fuel Bundles --» (placed into) --» Pressure Tubes
Saskatchewan has a large number of uranium deposits. In fact, Canada is the number one exporter of uranium.
Canadian Deuterium Uranium Reactor is one of the safest fission reactors in the world. It was developed by members of the AECL (Atomic Energy of Canada Limited).
Contain cylindrical rods made up of uranium oxide fuel pellets. These fuel bundles are placed in special pressure tubes inside the calandria.
The chemical symbol for heavy water is D2O. It contains deuterium which is an isotope of hydrogen. It is used as the moderator and the coolant in the CANDU reactor.
The entire cycle from mining the fuel to its disposal after use.
The waste material from the uranium ore after the uranium has been extracted. This material is slightly radioactive and must be disposed of with care.
Is an isotope of hydrogen that has one neutron in the nucleus,
Momentum is represented by the variable
. Momentum is the product of the mass and velocity 
.The total momentum of a system does not change.
This is one of the most fundamental principles in physics.
At a given location on the Earth and in the absence of air resistance all object fall with the same constant acceleration. g = 9.80 m/s2.
causes an object to change shape or accelerate. The SI units are
.Motion of an object with an inital velocity which is acted upon by only one force, the force of gravity.
Acceleration toward the center of circular motion. The units are m/s2
µ (mu) called the coefficient of friction is a constant. µk is used when the object is in motion (kinetic), and µs (mu) called the coefficient of friction is a constant. µs is used when the object is at rest (static)
FBD - Free Body Diagram. A diagram which has all of the external forces labeled on the object. Usually, Force Applied - Fa, Normal Force - FN, Force of Friction (either static or kinetic), Force of Gravity - Fg, and any angles.