TURBO TAKS
Week 6
Lesson 1: Body Systems
Lesson 2: Heat Transfer & Waves
Lesson 3: Energy & Electricity
Lesson 4: Motion, Forces, & Physics Equations
Lesson 1:
Body Systems
The Human Body
must also
maintain
homeostasis (a
balance).
The organs of the
body work together in organ
systems to perform specific
functions.
Organ systems are often
connected
and work
together to allow the body
to function.
Integumentary:
Skin, hair, nails:
Protects, prevents infection,
temperature control
Skeletal
Support and protection
of organs.
Muscular
Uses bones as simple
machines to exert force on the
body to create movement.
Nervous
Control system of the
body. Works with other
systems to maintain
homeostasis.
Endocrine
Secretes hormones
that circulate in the blood
stream and tell other systems
what to do.
Reproductive:
produces
gametes in ovaries and testis.
Circulatory:
transports
oxygen and nutrients to
cells and removes wastes.
Respiratory
Brings O
2
to
circulatory system and removes
CO
2
(gas exchange!).
Immune
Fights infection
Helper T

cells and macrophages turn
on the immune response and start
attacking invaders
.
Digestive:
breaks down
food and absorbs
nutrients
Excretory
Takes waste
from the blood stream for
removal from the body.
Lesson 2: Heat Transfer and
Waves
Heat Transfers
•
Heat moves from hot to cold.
•
Example: When you put your hand on a
lab table it feels cold because the heat in
your hand is leaving your body and
transferring down, into the table. Not the
other way around.
–
Heat from the 25
o
C block is sinking into the
10
o
C block
–
Heat does not rise, hot air rises.
10
o
C
25
o
C
Conduction
Conduction transfers from one substance to
another by
direct contact
of molecules.
THINK: Solids
Example: When you touch a hot stove!
25
o
C
5
o
C
slow transfer
wood
25
o
C
5
o
C
fast transfer
metal
Convection
Convection transfers heat through moving currents in
fluids (gases or liquids). Convection cannot occur in
solids, because solids can’t move.
•
THINK: Liquids and Gases
Hot liquids (and
gases) are less dense
and rise, causing
convection currents
.
These currents
transfer heat
throughout the
liquid (or gas).
Heat Source
Hot
Liquid
Rises
cooler
liquid
falls
cooler
liquid
falls
Much of the weather on earth
comes from convection currents.
The sun warms air at the surface
of the earth. Warm air rises,
causing winds. When the air
cools it falls back to the ground.
Hot air rises
Cold air is pulled in
from the sides
causing wind.
wind
wind
warm
ground
sunshine
Much of the
weather on earth
comes from
convection
currents. The sun
warms air at the
surface of the
earth. Warm air
rises, causing
winds. When the
air cools it falls
back to the ground
Radiation
•
Examples:
•
The sun warming your face.
•
Warmth you feel sitting
close to a campfire.
Radiation
Radiation transfers
heat through
electromagnetic waves
—
pure thermal energy.
All energy on earth comes
originally from the sun. Only
radiation can travel through the
vacuum of space to the earth.
Heat (thermal energy) in the form of
electromagnetic radiation from a light source.
Lets Practice
Name the type of heat transfer:
1.
Boiling water in a pot.
20
º
C
20
º
C
30
º
C
40
º
C
A
B
D
C
CONVECTION
3. McDonalds keeping french fries
warm under a heat lamp.
CONDUCTION
RADIATION
2. Your feet burning on concrete in the Summer time.
4. Which letter represents
a possible heat transfer?
D
(Always
hot
.
cold)
Waves
A wave is any disturbance that transmits
energy through matter or space
Types of Waves
1.
2.
Types of Waves
•
1. Compression/ Longitudinal wave
•
Produced by moving a slinky spring back and
forth.
•
Example: Sound
Types of Waves
•
2. Transverse Wave
•
Produced by waving
a rope or other medium
up and down
•
Example: Light wave, or a ripple in a pond
Parts of a Transverse Wave
Characteristics of All Waves
•
Wavelength

distance from a point in a wave to
the next point on the next wave in the same phase
•
Frequency

the number of times that a repeated
event occurs per second
•
For sound, High pitch
= high frequency
•
V = f
λ
(Velocity = frequency x wavelength)
Short Wavelength = High
Frequency
Long Wavelength = Low
Frequency
Wave Properties
•
Reflection
•
When waves bounce
off a hard boundary.
•
The sound waves are
bouncing off the tank.
(i.e.

mirror, echo)
•
Refraction
•
The bending of light as it passes from
one medium into another. (i.e.

lenses)
Wave Properties
•
Diffraction
•
Occurs when a wave bends
around a corner.
•
Interference
•
A wave
interaction that
occurs when
two or more
waves overlap.
Click screen when ready…
Wave Properties
•
Resonance
•
Occurs when one object vibrates because of
another object’s vibrations.
•
Common in tuning forks and other musical
instruments
•
Example: Ear
hearing
•
Body of guitar vibrates
because of it’s strings
vibration.
Click screen when ready…
Make sure sound is turned down.
Lets Practice
•
Answer with: Reflection, Refraction,
Diffraction, Interference, or Resonance.
1. Lenses
2. Using a mirror
3. Water waves passing
through an opening.
4. When the
primary colors of
light combine to
form white light
5. When singing
near a piano, the
keys can start to
sound.
REFRACTION
REFLECTION
DIFFRACTION
INTERFERENCE
RESONANCE
Lesson 3: Energy and
Electricity
Energy
•
Energy is the ability to cause motion or forces; the
units of energy are
joules (J).
Potential Energy
•
1.
Gravitational Potential Energy
(in Joules, J) is
stored energy, because an object is above the ground.
•
More height = more Potential Energy. It has the
potential
to cause motion and forces.
•
Gravitational Potential Energy= mass x
gravity
x height
E
p
= mgh
Potential energy equals
mass times gravity times height.
Potential
Energy
(
in
Joules
)
mass (
in
kilograms
)
height (
in
meters
)
acceleration due to
gravity (
9.8 m/s
2
)
Potential Energy
•
The acceleration due to
gravity
we
experience on Earth is 9.8 m/s
2
. In
space, gravity is 0 m/s
2
.
•
Potential Energy Practice: PE=mgh
Don’t forget
to use the
given
constants and
formulas!
Ex: How much potential energy does a 4 kg object have that
is 5 meters off the ground?
E
p
= mgh
E
p
= (4)(10)(5)
= (40)(5)
= 200 Joules
takes 5,000 J of energy)
m = 4 kg
h = 5 m
g = 10 m/s
2
E
p
= ?
m =
h =
g =
E
p
=
Kinetic Energy
•
Kinetic Energy
(in Joules, J) is the energy of
motion. Moving objects have kinetic energy.
•
Kinetic Energy=
½
mass x velocity
2
•
Mass is measured in kilograms (kg) and velocity is
measured in meters/second (m/s).
E
k
= (
½)
mv
2
Kinetic energy equals one

half
Times mass times velocity squared.
Kinetic
Energy
(
in
Joules
)
mass (
in
kilograms
)
velocity (in
m/s
)
Energy Transfers
•
Work
(in Joules, J) is
how forces change
energy.
•
Work=
Force x Distance
•
Power
(in Watts, W)
is how fast work is
done.
•
Power =
Work
Time
W = Fd
Work
(in
Joules)
Force (in
Newtons)
Distance (in
meters)
P = W/T
Power
(in
Watts)
Work (in
Joules)
Time (in
seconds)
•
Energy can be transferred from one type to another.
Efficiency
(in %)
Energy gained by
the object (in J)
Energy you tried to give
the object (in J)
x100
out
in
W
Eff
W
Efficiency
•
Efficiency
is the percentage of energy retained (not
lost) in an energy transfer.
Efficiency Calculation
Work In:
Work Out:
How much
energy you tried to
give
to the object thru an energy
transfer or work.
How much
energy
is
actually
gained
by the object
(how much it got out).
Here work is done on
the object, pulling it
up the ramp. This is
the total energy that
you tried to give the
object.
Work put
in 240 J.
2 m
After
10
kg
The object
only
got out 200 J.
x100
x100
200 J
x100
240 J
.83 x 100
= 83%
out
in
p
W
Eff
W
E
Eff
W
W
in
=Fd=
30(8)=240 J
W
out
=Ep
gained
=mgh
=10(9.8)2
=98(2)
= 196J
196
.82 x 100
=82%
Types of Energy
•
Thermal Energy
—
Heat
energy. A product of most
other forms of energy.
•
Mechanical Energy
—
Any
kind of Kinetic (moving) or
Potential (height) Energy.
•
Chemical Energy
—
Stored in
chemical bonds. Includes
energy in food, plants, and
batteries (produce electricity
by combining chemicals).
•
Electrical Energy
—
Energy of
moving electrons: lightening,
electricity.
•
Radiant Energy
—
Light energy
from light bulbs or the sun
(renewable solar energy).
•
Nuclear Energy
—
Energy from
nuclear reactions (radiation):
makes huge amounts of energy,
but also long

term, radioactive
waste like power plants.
Lets Practice
WORD BANK
a)
Kinetic Energy
b)
Potential Energy
c)
Energy
d)
Height
e)
Joules
Match with the terms to the right:
1.
The units for energy.
2.
The ability to create forces or motion.
3.
Energy because of an object’s motion.
4.
Energy because of an object’s position above
the ground due to gravity.
5.
Vertical distance above the ground.
Electricity
•
Moving of electrons through conductors.
The path must be closed, or electrons
cannot move.
Electrical Circuits
•
Series Circuit
•
Provides a single
conducting pathway
without junctions.
•
Parallel Circuit
•
When two or more components of
a circuit are connected across
junctions, providing separate
pathways for the current.
Which type of circuit would you rather have for your Christmas lights?
Parallel, so that if one light burns out, the current can still reach
the other bulbs.
Assuming the chart contains all energy transformations in the
Earth system, how much solar radiation
goes toward evaporating water?
F
40,000 terajoules
G
92,410 terajoules
H
121,410 terajoules
J
133,410 terajoules
Subtract all the energy
expenditures from the
total amount reaching
Earth.
173,410
–
52,000

81,000
–
370
–
40 = 40,000
Lesson 4: Motion, Forces, and
Physics Equations
Speed and Velocity
•
Speed
is the distance an object travels per
second.
•
Velocity
includes the
speed
of an object and
the
direction
of its motion.
•
They share a formula on your equation sheet.
d
s
t
Speed equals the distanced traveled
divided by the time it took to move that
distance.
Distance travelled
(
in meters
)
Time
(
in seconds
)
Speed
(
in
meter/sec
)
v =
d
t
Measuring Speed
To measure speed you must determine the
distance traveled and the elapsed time.
Initial Position
Final Position
25 m
Distance Traveled
0:05.0
Elapsed Time
5 sec
0:00.0
25m
5m/s
5sec
D
S
T
Acceleration
a
=
Acceleration equal change of velocity
divided by change of time
.
Change of
Velocity
(in meters/sec)
Change of
Time
(in seconds)
Acceleration
(in m/s
2
)
, so,
final initial
final initial
V V
V V V a
T
a =
a =
Δ
V
Δ
T
An object accelerates when it changes speed OR changes
direction!
If acceleration is unknown use acceleration due to
gravity out of the constants box on the formula chart!
Acceleration
is how fast you change velocity OR how much the
velocity changed in a certain amount of time.
Solving for Acceleration
1. Calculate initial velocity
8m
1sec
8m/s
f
final
D
V
T
V
4m
1sec
4m/s
i
initial
D
V
T
V
2
8 4
2
4
2m/s
2
f i
initial
V V
a
T
V
Accelerates for
2 seconds
4 m
Measure V
f
(Final Velocity)
8 m
Measure V
i
(Initial Velocity)
Measure
Δ
T
(Time it took to
Accelerate)
0.0
1.0
3.0
4.0
3. Determine the change in time.
2. Calculate final velocity
4. Plug into acceleration equation.
So
Δ
T = 2 sec
MOMENTUM
•
Momentum
is how hard it is to stop something and is a
product of an object’s mass and its velocity. Momentum
is increased if either the mass or velocity is increased.
p =
mv
Mass (in kg)
Velocity (in m/sec)
Momentum
(in
kgm
/sec)
Momentum equals
mass times velocity
.
Momentum
The canon ball has a
smaller mass and a larger
velocity. The canon has a
larger mass and a smaller
velocity. However, since
the system started with a
net momentum of zero,
the momentums of the
objects afterwards must
be equal and opposite to
cancel each other out,
or = 0.
P
canon
= P
canon ball
Forces
•
A
force
is a push or pull that one body exerts
on another. Force is measured in Newtons (N).
•
Forces can add and subtract.
15 N
65 N
10 kg
Total Net Force
= +65

15
= 50 N
Right is positive.
Left is negative.
Newton’s Laws of Motion:
1.
An object in motion will stay
in motion unless a force acts
upon it. (Law of Inertia). If
an object is at rest, it will
stay at rest until acted upon.
*Why we need seatbelts.
2.
Force = mass x acceleration
*Why a bowling ball does not
go as fast as a ping pong ball
when the same force is
applied.
3. For every action there is an
equal and opposite reaction.
*Why a rocket goes up when
gasses push down.
Inertia
Inertia is the tendency to not change
motion, and is dependent only on the
object’s mass (measured in kilograms).

Newton’s First Law.
Object’s with more
mass have more inertia
and are harder to push.
Object’s with less
mass have less inertia
and are easier to push.
Frequent Equations from the Formula Sheet
Solving Physics Problems:
1.
Identify what is being asked and
underline
or
highlight
it.
2.
Find the appropriate formula and
write it
down
in your test booklet.
3.
Plug in the
known
information
(
WRITE IT OUT
).
4.
Solve
for the unknown.
Lets Practice the Steps Together…
•
What is the approximate difference in
gravitational potential energy
of a 2kg
object 3m off the ground and a 2kg object
1m off the ground?
•
F) 19J
•
G) 39 J
•
H) 59 J
•
J) 79 J
First Situation
PE=mgh
PE=(2)(9.8)(3)
PE= 58.8 J
Second Situation
PE=mgh
PE=(2)(9.8)(1)
PE= 19.6 J
Difference Between=
58.8
–
19.6 = 39.2 J
or approximately
39J = G
gravitational potential energy
The illustration above shows a student about to throw a ball while
standing on a skateboard. Which illustration below correctly shows the
skateboard’s direction of motion after the student releases the ball?
A
B
C
D
skateboard’s direction of motion
•
A cyclist moves at a constant speed of 5
m/s. If the cyclist does not accelerate during
the next 20 seconds, he will travel
—
•
A 0 m
•
B 4 m
•
C 50 m
•
D 100 m
They are asking for distance
and giving us speed and time.
S=d/t
5=d/20
(Multiply by 20 on each
side of the equal sign.)
20 x 5= 100m = D
•
How much work is performed when a 50 kg
crate is pushed 15 m with a force of 20 N?
•
F
300 J
•
G
750 J
•
H
1,000 J
•
J
15,000 J
work
W=Fd
W= (20)(15)
W= 300 J = F
Watch out for extra information!
Levers
Which lever arrangement requires the least
effort force to raise a 500 N resistance?
A mechanic used a hydraulic lift to raise a
12,054 N car 1.89 m above the floor of a
garage. It took 4.75 s to raise the car. What
was the power output of the lift?
•
A) 489 W
•
B) 1815 W
•
C) 4796 W
•
D) 30,294 W
This is a two part calculation.
You’re looking for Power, but must have
work before you can solve (P=w/t)
1.
Calculate work:
w=fd
w=(12054)(1.89)
w=22,782.06 J
2. Calculate power:
P=w/t
p=(
22,782.06
)
(4.75)
P=4796.22 W
We know it’s a force because it’s
measured in Newtons!
•
A ball moving at 30 m/s has a momentum
of 15 kg∙m/s. The mass of the ball is
—
•
A
45 kg
•
B
15 kg
•
C
2.0 kg
•
D
0.5 kg
momentum
Momentum = mass x velocity
P=mv
15=m(30)
Divide by thirty on both sides.
15/30= 0.5 kg = D
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