Energy and transformation Flashcards
What is the definition of energy?
-The capacity to do work or to produce change
What form of measurement is used to measure energy?
One “Joule” or “J” represents the energy needed to lift an object weighing 1 Newton (N) to the height of 1 meter. An object that weighs 1 N has a mass of 100 grams. The formula is:
Joules= Newtons x Meters
Grams= Newtons x 100
Newtons= Joules
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What are the different forms of energy and their sources?
- Solar energy-the sun
- elastic energy-wire spring
- Electrical energy-power station
- thermal energy-fire
- radiant energy-electric light bulb
- chemical energy-living cell
- mechanical energy-moving vehicle
- wind energy-wind
- sound energy-sound
- hydraulic energy-waterfall
- nuclear energy-nucleus of atom
What is thermal energy?
What are two factors affecting thermal energy?
Thermal energy is the energy that comes from the random motion of particles that make up a substance.
1) the higher the temperature of a substance, the faster the particles are moving, the higher the thermal energy
2) the more particles in a substance, the more collisions occurring, the more thermal energy
What are examples of work or change accomplished by thermal energy?
- melting of snow by the heat of the sun (solid)
- production of water vapour by the boiler of a steam engine in order to move the train (liquid)
- the lifting of a hot air ballon into the sky by the burners heating of air inside the ballon (gas)
What is radiant energy?
Radiant energy is the kind of energy that is contained in and transported by electromagnetic waves. (Any waves part of the electromagnetic spectrum).
Ex: listen to the radio, cook with a microwave, get a tan, get an X Ray
How does the wavelength depend on the energy?
When a wavelength is shorter, the energy frequency is higher
When a wavelength is longer, the energy frequency is lower
What do electromagnetic waves do in energy?
They transfer energy from one place to another.
Does energy creation exist?
No, no energy can be created or destroyed, only transformed
What is chemical energy?
It is the energy stored in the bonds of a molecule.
- An atom is the smallest particle of matter, and cannot be divided
- A molecule is a group of two or more atoms held together by chemical bonds
Does chemical energy do work or create change?
No, but to get the energy out, it must be broken. So the more bonds a molecule has, the stronger it is
What is photosynthesis?
When the suns energy is transformed into chemical energy and is stored in the bonds of a sugar molecule (glucose)
What is cellular respiration?
It helps living organisms use the energy stored in sugar molecules so they can grow, move and think. Cellular respiration converts nutrients into adenosine triphosphate
What is mechanical energy?
The energy that results from the speed of an object, its mass and its relationship to its surroundings.
(It is the energy of motion that does the work)
How does speed affect mechanical energy?
Mechanical energy increases with speed.
Ex: the damage caused by a car crash with the car going 100km/h is much greater than a crash at 20km/h