Law of conservation of energy Flashcards
(67 cards)
1
Q
The sum of the kinetic and potential energy of the particles that make up an object
A
Thermal energy
2
Q
transfer of energy by electromagnetic waves
A
Radiation
3
Q
Transfer of thermal energy by collisions between the particles that make up matter
A
Conduction
4
Q
Transfer of thermal energy in a fluid by the movement of warmer and cooler fluid from one place to another
A
Convection
5
Q
stove
A
thermal energy
6
Q
toaster
A
Thermal energy
7
Q
Ironing clothes
A
Conduction
8
Q
Ice melting,
A
Conduction
9
Q
Iron
A
Thermal energy
10
Q
hot air balloons,
A
Convection
11
Q
x-rays,
A
Radiation
12
Q
Computer CPUs
A
Conduction
13
Q
Car Engine Cooling,
A
Conduction
14
Q
remote controls.
A
Radiation
15
Q
Fireplace
A
Thermal energy
16
Q
metal spoon
A
Conduction
17
Q
ultraviolet light,
A
Radiation
18
Q
Lighting a Match
A
conduction
19
Q
Hot Coffee in a Mug.
A
conduction
20
Q
Wi-f- signals, remote controls, MRI scans
A
Radiation
21
Q
cooking on a gas stove
A
Conduction
22
Q
Boiling water,
A
Convection
23
Q
radio waves,
A
Radiation
24
Q
Sea and ocean currents,
A
Convection
25
cooking in ovens,
Convection
26
Hair dryers,
Convection
27
Microwave
Thermal energy
28
greenhouse effect
Convection
29
sunlight
Radiation
30
microwave ovens,
Radiation
31
MRI scans
Radiation
32
First Law of Thermodynamics states that if the mechanical
energy of a system is ___,
the increase in thermal energy of
that system equals the ___
1.constant,
2.sum of
the thermal energy transfers into
that system and the work done
on that system.
33
Second Law of Thermodynamics states that energy ___. Systems always
move to more stable ___
1.spontaneously
spreads from regions of higher
concentration to regions of lower
concentration.
stable states, or
states with uniform energy
distribution.
34
Example of 1st law
Increase temperature of your
hands by warming them near a fire and by
rubbing them together
35
2nd law example
Heat from radiator transfers to
cat but not the reverse
36
The faster particles move,____
the higher the thermal
energy and the warmer an object becomes.
37
Greenhouses use s____ to____. Heat
enters the greenhouse through its covering of ___ and starts to warm the ___.
The warmed air near the soil begins to ____ and is
immediately replaced with _____. This cycle raises the temperature
inside the greenhouse more rapidly than the air outside,
creating a sheltered, warmer microclimate
1.solar radiation to trap heat
2. covering of glass or
plastic
3.soil and plants inside
4.rise
5.cooler surrounding air that
starts to heat up
38
A vacuum is an extremely ____. a vacuum between the two outer walls of a thermos bottle ___. It limits or
reduces the transfer of energy between
the bottle’s contents and its surroundings.
This keeps the temperature of the
contents of the thermos at its original
temperature.
1.Good insulator
2.minimizes the transfer of thermal energy from conduction and convection.
39
If a piece of paper is placed between two colliding spheres as shown below, holes will
be burned in the paper where the steel spheres meet. Describe all the
transformations of energy between the two steel spheres and the paper.
1.After the spheres collide, the
particles of matter in the spheres
begin to vibrate faster which
increases the thermal energy of
the particles.
2. The force of the colliding spheres
causes the thermal energy of the
paper to increase, which burns the
hole in the paper
40
Identify and give an example of 3 ways electrical energy is
converted to other types of energy such as mechanical,
light, thermal, or sound energy
Identify and give an example of 3 ways electrical energy is
converted to other types of energy such as mechanical,
light, thermal, or sound energy
41
Mechanical
1.Can opener
2.Mixer
3.Drill
42
Light
1.flashlight
2.lamp
3.car headlight
43
thermal
1.toaster
2.oven
3.hair dryer
44
Sound
1.radio
2.cell phone
3.alarm clock
45
Potential Energy-
stored energy
46
formula
PE = m*g*h
47
m
mass in kilograms
48
g
acceleration due to gravity (9.8 m/s2)
49
h
height in meters
50
Units
(kg*m/s2)*m = newton*meter = Joules
51
Calculate the boulder’s
gravitational
potential energy at its
highest point.
Boulder’s mass is 8 kg.
Distance A is 20 m.
Distance B is 10 m
Calculate the boulder’s
gravitational
potential energy at its
highest point.
Boulder’s mass is 8 kg.
Distance A is 20 m.
Distance B is 10 m
52
Kinetic energy
energy of motion
53
formula
~KE = ½ mv2
54
m
mass in kilograms
55
v
velocity in meters/sec
56
Units
(kg*m/s2)*m = newton*meter = Joules
57
Example:
The bird has a mass of 2 kg. It is flying at a
velocity of 5 m/s East. Find its kinetic
energy.
KE = ½ mv2
Example:
The bird has a mass of 2 kg. It is flying at a
velocity of 5 m/s East. Find its kinetic
energy.
KE = ½ mv2
58
Kinetic & potential energy convert
to one
another = energy not lost or gained.. Just
transferred
59
Types of Potential Energy:
Elastic, Chemical and Gravitational
60
Energy Transformations in Roller Coasters
Energy Transformations in Roller Coasters
61
Transformation #1
mechanical energy used to move the roller coaster cars to the top of
the first hill so mechanical energy to kinetic energy
62
Transformation #3
mechanical energy is once again used to bring the roller coaster cars to
a stop at the end of the ride. Friction of metal brakes may produce
thermal energy.
63
Transformation #2
at the top of the hill the roller coaster car has a great amount of
gravitational potential energy that is transformed into kinetic energy as
the roller coaster cars go down the hill
64
10. Three ways that wind turbines
transform energy.
Kinetic Energy to Mechanical Energy:
wind flows past the turbine blades causing
them to rotate
Mechanical Energy to Electrical Energy:
electrical energy
Rotating blades then turns a generator to produce
3) Power conversion and distribution:
electricity generated is converted to alternating current (AC) and
transmitted through power lines to homes and businesses
65
Elastic Potential Energy
Energy stored in objects that can be stretched or compressed, like springs or rubber bands.
66
Chemical Potential Energy
Energy stored in the bonds between atoms and molecules, released during chemical reactions.
67
Gravitational Potential Energy
Energy an object has due to its height above the ground, depending on its mass and height.
