Transcript Conduction, convection or radiation???

Force and Motion
Objective: determine how force
affects the motion of an object
Force & Motion
9-11-12
• Focus Question: What happens to an
object when an unbalanced force acts
upon it?
• Prediction:
• Procedure: Follow the directions
• Data
Force and Motion
1. What is force?
2. How does force affect the motion of an
object?
3. What is net force?
4. How does a balanced force affect the
motion of an object?
5. How does an unbalanced force affect the
motion of an object?
Net Force is the overall force acting on an
object.
For example, if there is a 10N force acting
upwards, and a 5N force acting downwards, then
the net force is 5N upwards.
A Force is any influence that causes an
object to undergo a change in speed, a
change in direction, or a change in shape.
An example of Force is a cart being pulled up a
hill.
Calculate the net force of each object.
Determine if the force is balanced or unbalanced and
describe the affect on the motion of the object.
6.
200 N
200 N
7.
200 N
400 N
Calculate the net force of each object.
Determine if the force is balanced or unbalanced and
describe the affect on the motion of the object.
8.
800 N
200 N
9.
800 N
400 N
200 N
Calculate the net force of each object.
Determine if the force is balanced or unbalanced and
describe the affect on the motion of the object.
10.
800 N
1000
N
11.
800 N
1000
N
200 N
400 N
speed:
how fast something is going
speed = distance
time
s=d
t
remember speed is measured in our cars in
miles per hours (per means divide)
12) JJ runs 24 miles in three hours.
What is his speed?
BE SURE TO INCLUDE UNITS!!!
Velocity is speed with direction….
Are each of the following speed or velocity?
13) Quansha driving her low-rider Impala
30 miles per hour is ______….
14) Claire driving her low-rider Impala 30 mph
south on Kuykendahl is _______!
15) Colby is driving his Ferrari 120 miles
per hour north on I-45. Speed or velocity?
Energy Types….
kinetic
(mechanical)
sound
potential (chemical)
electrical
potential (kinetic)
light
heat
potential (kinetic) – the ability to release
energy due to an object’s location
mechanical/kinetic – energy of motion
sound – energy traveling in waves
or vibrations through the air
potential (chemical) – energy stored
in the chemical bonds of
compounds
chemical – energy released by
breaking the bonds in
compounds
electrical – energy created by moving
electrons
heat – energy given off as thermal
radiation
light – energy from the movement
of electromagnetic waves
List the energy transformations for
the following:
16) flashlight
17) toaster oven
Movement of heat energy……
convection: movement of energy
by the mass movement of particles
(like hot air rises!)
conduction: transfer of energy from
particle to particle.
radiation: movement of energy by
electromagnetic waves (light)
18) What type of heat transfer is being
described when the fireman tells Morgan
to touch the door to see if it is hot before
opening it (but not the door knob)?
Conduction, convection or radiation???
19) What type of heat transfer is being
described when Colton lays in the sun
and works on his tan?
Conduction, convection or radiation???
20) What type of heat transfer is being
described: Jay visits “Balloons Over
Houston” and watch the hot air balloons
float away?
Conduction, convection or radiation???
21) What type of heat transfer is being
described: Megan enjoys warming her
hands up by the campfire on a cold
winter night.
Conduction, convection or radiation???
Newton’s 3 Laws….
First Law: An object in motion
will remain in motion…an object at
rest will remain at rest…unless acted
upon by an unbalanced force.
second law: the acceleration of an
object is directly proportional to
the force acting on it and inversely
proportional to its mass
in other words: F = ma
where
F is force
m is mass
a is acceleration
third law: for every action, there is
an equal and opposite reaction.
aka: action/reaction
Which Law is described by the following:
22) Winston notices it is easier to push
his ’69 Mustang than his ‘012 SUV
Which Law is described by the following:
23) Ximena is driving her snowmobile;
she hits a patch of ice and skids through
a turn.
Which Law is described by the following:
24) A bullet hurts a lot more when
it is shot out of a gun rather than thrown
at you!
Which Law is described by the following:
25) A rocket shoots up in the air by
“whooshing” massive amounts of
exhaust downwards.
simple machines…..
simple machines…..
wheel & axle
wedge
pulley
lever
incline plane
screw
simple machines do NOT change
the amount of work….
they either reduce the input force
or change the direction of the
force needed.
If the force is reduced, the distance
of the effort is increased!