Material Science Lecture Notes

Flashcards about general material science

What is energy?

The ability of a system/object to do work.

What is the energy conservation principle?

Energy cannot be created nor destroyed

What is energy transformation?

Change from one form of energy to another, but the total energy remains the same.

List the forms of energy

Kinetic, Gravitational potential, Elastic potential, Chemical, Electrical, Nuclear, Light, Sound, Heat

What is kinetic energy?

Energy of a moving object

What is gravitational potential energy (GPE)?

Energy due to an object's height.

What is the formula for potential energy?

mass x g x height, where g is the gravitational constant (10 m/s²)

What is elastic potential energy?

Energy stored in a stretched or compressed object, like a spring.

What is chemical energy?

Energy contained in food or fuel.

What is electrical energy?

Energy in the flow of electrons.

What is nuclear energy?

Energy released when the nucleus of an atom splits.

What is light energy?

Energy given out by any hot object.

What is sound energy?

Energy given out by vibrating objects.

What is heat energy?

Energy contained in any hot or warm object.

What do Sankey diagrams show?

Visualize energy transfer, showing useful energy versus wasted energy.

What are non-renewable energy sources?

Fossil fuels (coal, oil, and natural gas) and nuclear fuels (uranium and plutonium).

What are renewable energy sources?

Wind, waves, tides, hydroelectric, biofuels, geothermal, and solar energy.

What are the three stages of electricity generation?

Boiler, Turbine, Generator

What happens in the boiler stage of electricity generation?

Fuel burns to heat water and turn it into steam.

What is the function of the turbine in electricity generation?

Steam makes the turbine spin.

What is the function of the generator in electricity generation?

Converts the movement of the turbine (kinetic energy) into electricity.

How is fossil fuels used in energy generating?

Releasing heat energy to turn water into steam.

How are biofuels used in energy generating?

Renewable energy sources (solids, liquids, or gases) are burned to turn water into steam.

How is Nuclear energy used in energy generating?

Nuclear fission releases a lot of heat energy. Water is used as a coolant to take away this heat energy

How is Wave Power used in energy generating?

Waves provide up and down motion to directly drive a turbine linked to a generator.

How is Hydroelectric power used in energy generating?

Flooding a valley forms a reservoir behind a big dam. Water released from the reservoir falls through the dam and turns the turbines.

How is Geothermal energy used in energy generating?

Cold water is pumped in pipes down to hot rocks and returns as steam to drive the turbines.

How are solar cells panels used in energy generating?

Solar cells generate electricity directly from sunlight.

Why our sun radiates energy?

radiates energy because of nuclear fusion reactions deep inside

What is the formula for efficiency?

(useful energy output / energy input) x 100% or (useful power output / power input) x 100%

When is Work done?

Whenever a force makes something move.

What is the equation for Work done?

force x distance

What is the definition of Power?

The rate at which work is done

What is the equation for Power?

work done / time taken or energy transformed / time taken

What is the equation for kinetic energy?

1/2mv^2 , where m is mass and v is velocity

What are waves?

Transmission of disturbance from one point to another with energy transfer.

What is the formula for Wavelength?

Distance / Number of waves in that distance

What is the formula for wave speed?

Distance / Time, Frequency * Wavelength

What is the formula for Frequency?

1 / period

What is the formula for Period?

Time / Number of waves

What are the two main types of waves?

Transverse and Longitudinal

What are Transverse waves?

Oscillations are at right angles to the direction in which the energy is traveling (perpendicular).

What are Longitudinal waves?

Oscillations are in the direction of travel

List Electromagnetic Spectrum Waves from longest to shortest

radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma rays.

What is reflection of light?

Bouncing of light from a surface.

What is refraction of light?

Bending of light as it passes from one medium to another.

What is Dispersion?

Splitting of white light into its component colors (spectrum).

What is the equation for Critical Angle Formula?

sin(c) = 1 / n

What is the equation for Echo Formula?

(v × t) / 2

What is Radioactivity?

spontaneous emission of radiation from unstable atomic nuclei