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EQ: How do forces affect motion?
Unit 3:Forces EQ:How do forces affect motion? The Meaning of Force
Force:a push or pull upon an object resulting from the objects
interaction with another object. Force is a vector quantity. For
simplicity sake, all forces (interactions) between objects can be
placed into two categories: Contact Forces Action-at-a Distance
Forces Contact Forces:those types of forces that result when two
interacting objects are perceived to be physically contacting each
other. Action-at-a-Distance Forces:those types of forces that
result even when the two interacting objects are not in physical
contact with each other, yet are able to exert a push or pull
despite their physical separation. Newton:the amount of force
required to give a 1-kg mass an acceleration of 1 m/s2. The
standard unit of measurement for force. 1 Newton (N) = 1 kg m/s2
Action-at-a-Distance Forces
Types of Forces Contact Forces Action-at-a-Distance Forces
Frictional Force Gravitational Force Tension Force Electrical Force
Normal Force Magnetic Force Air Resistance Force Applied Force
Spring Force Fapp Fnorm Ffrict Fair Ftens Fspring Type of Force
Description Symbol
Applied Force A force that is applied to an object by a person or
another object. Fapp Gravitational Force The force with which the
earth, moon, or other massively large object attracts another
object towards itself.Gravity is directed downward toward the
center of the earth. The weight of an object. Fgrav = mg m= mass in
kg g= 9.8 N/kg Normal Force The support force exerted upon an
object that is in contact with another stable object.(Ex. Book on a
desk) Fnorm Friction Force The force exerted by a surface as an
object moves across it or makes an effort to move across
it.(Sliding, static) Ffrict Air Resistance Force A special type of
force that acts upon objects as they travel through the air.It
opposes the motion of the object. Fair Tension Force The force that
is transmitted through a string, rope, cable or wire when it is
pulled tight by forces acting from opposite ends. (Tug-of-War)
Ftens Spring Force The force exerted by a compressed or stretched
spring upon any object that is attached to it. Fspring Types of
Friction Sliding Friction:results when an object slides across a
surface. (Ex:pushing a box across a floor) Static Friction:results
when the surfaces of two objects are at rest relative to one
another and a force exists on one of the objects to set it into
motion relative to the other object. (Ex:pushing a couch across a
carpeted floor - what you must overcome in order to get the couch
to move) Fluid Friction: results when a solid object moves through
a fluid
Fluid Friction:results when a solid object moves through a fluid.
(Ex:bird flying through the air, fish moving through water) Rolling
Friction:results when an object rolls across a surface. (Ex:bicycle
wheel rolling over the road) Mass vs. Weight The force of gravity
acting upon an object is sometimes referred to as the weight of the
object.It is related to the pull of gravity on the object and is
altered by location. The mass of an object refers to the amount of
matter that is contained by the object. Mass is never altered by
location, the pull of gravity, speed, or even the existence of
other forces. Check Your Understanding
Different masses are hung on a spring scale calibrated in
Newtons.(Fgrav = mg) The force exerted by gravity on 1 kg = 9.8N.
The force exerted by gravity on 5 kg = _____N. The force exerted by
gravity on _____kg = 98N. The force exerted by gravity on 70 kg =
_____N. 2)When a person diets, is their goal to lose mass or to
lose weight? Explain. Drawing Free-Body Diagrams
Free-Body Diagrams:diagrams used to show the relative magnitude and
direction of all forces acting upon an object in a given situation.
The size of the arrow in a free-body diagram reflects the magnitude
of the force while the tip of the arrow shows the direction that
the force is acting. Fnorm Ffrict Fapp Fgrav Guided Practice A book
is at rest on a tabletop. Diagram the forces acting on the book. A
girl is suspended motionless from the ceiling by two ropes. Diagram
the forces acting on the combination of girl and bar. An egg is
free-falling from a nest in a tree. Neglect air resistance. Diagram
the forces acting on the egg as it is falling. A flying squirrel is
gliding (no wing flaps) from a tree to the ground at constant
velocity. Consider air resistance. Diagram the forces acting on the
squirrel. Graded Practice A rightward force is applied to a book in
order to move it across a desk with a rightward acceleration.
Consider frictional forces. Neglect air resistance. Diagram the
forces acting on the book. A rightward force is applied to a book
in order to move it across a desk at constant velocity. Consider
frictional forces. Neglect air resistance. Diagram the forces
acting on the book. A college student rests a backpack upon his
shoulder. The pack is suspended motionless by one strap from one
shoulder. Diagram the vertical forces acting on the backpack. A
skydiver is descending with a constant velocity
A skydiver is descending with a constant velocity. Consider air
resistance. Diagram the forces acting upon the skydiver. A force is
applied to the right to drag a sled across loosely packed snow with
a rightward acceleration. Neglect air resistance. Diagram the
forces acting on the sled. A football is moving upwards towards its
peak after having been booted by the punter. Neglect air
resistance. Diagram the forces acting upon the football as it rises
upward towards its peak. A car is coasting to the right and slowing
down. Neglect air resistance. Diagram the forces acting upon the
car. Determining Net Force Net Force:the vector sum of all the
forces that act upon an object. = = 0 = = = 5 5 10 5 -5 5 10 15 5
-10 -5 5 -15 -10 -5 5 10 Guided Practice 1200 N 50 N 600 N 20 N 800
N 50 N 800 N Fnet = 400N up
Fnet = 200N down Fnet = 20N left Does a Net Force Exist? Graded
Practice 1 3N 3N A B 5N 5N 5N 3N 3N 40N 20N C D 20N 25N Graded
Practice 2 300N B Fnet = 0 N Fnet = 60N, left A 50N 80N D
200N
Fnet = 900N, up Fnet = 30N, right 200N H Forces Practice Worksheet
1 Design an Experiment Activity Formative Assessment 1 Sir Isaac
Newton Biography https://www.youtube.com/watch?v=YPRV1h3CGQk
Newtons First Law of Motion
Isaac Newton, a 17th century scientist, put forth a variety of laws
that explain why objects move (or dont move) as they do. These laws
are known as Newtons Three Laws of Motion. Newtons First Law of
Motion: an object at rest stays at rest and an object in motion
stays in motion with the same speed and in the same direction
unless acted upon by an unbalanced force. Sometimes referred to as
the law of inertia. (same speed and direction)
Forces are Balanced Stay in Motion (same speed and direction)
Objects in Motion (v 0 m/s) Objects at Rest (v = 0 m/s) Stay at
Rest a = 0 m/s2 a = 0 m/s2 Balanced vs. Unbalanced Forces
Balanced Forces:Equal in magnitude, opposite in direction.Also
known as equilibrium. Unbalanced Forces:Forces not in equilibrium.
Inertia: the resistance to a change in motion.
Everyday Examples of Newtons First Law: A car stopping suddenly.
The force of the road on the locked wheels provides the unbalanced
force to change the cars state of motion, yet there is no
unbalanced force to change your own state of motion. Thus, you
continue in motion, sliding along the seat in forward motion. What
stops you from continuing through the windshield? Your seat belt!
The seat belt provides the unbalanced force that brings you from a
state of motion to a state of rest. Blood rushes from your head to
your feet while quickly stopping when riding on a descending
elevator. A brick is painlessly broken over the hand of a physics
teacher by slamming it with a hammer. (Dont try this at home!) To
dislodge ketchup from the bottom of the ketchup bottle, it is often
turned upside down and thrusted downward at high speeds and then
abruptly halted. Headrests are placed in cars to prevent whiplash
injuries during rear-end collisions. While riding a skateboard (or
wagon or bicycle), you fly forward off the board when hitting a
curb or rock or other object that abruptly halts the motion of the
skateboard. Inertia and Mass Before Newton, it was believed that it
was the natural tendency of an object to come to rest. Eventually
moving objects would stop moving; a force was necessary to keep an
object in motion. Galileo, a premier scientist in the 17th century,
developed the concept of inertia. He reasoned that moving objects
eventually stop because of a force called friction. In experiments
using a pair of inclined planes facing each other, Galileo observed
that a ball would roll down one plane and up the opposite plane to
approximately the same height. If smoother planes were used, the
ball would roll up the opposite plane even closer to the original
height. Galileo reasoned that any difference between initial and
final heights was due to the presence of friction. He postulated
that if friction could be entirely eliminated, then the ball would
reach exactly the same height each time. He further observed that
regardless of the angle in which the planes were oriented, the
final height was almost always equal to the initial height. If the
opposite incline were elevated at nearly a 0-degree angle, then the
ball would roll almost forever in an effort to reach the original
height. Isaac Newton built on Galileos thoughts about motion
Isaac Newton built on Galileos thoughts about motion. His first law
declares that a force is not needed to keep an object in motion,
rather one is needed to get it to stop. In the absence of friction,
an object would continue in motion with the same speed and
direction forever! All objects resist change in motion but some
have more of a tendency to resist change more than others. The
tendency of an object to resist changes in its state of motion
varies with mass. The more mass an object has, the more inertia it
has.
https://www.youtube.com/watch?v=T1ux9D7-O38 Check Your
Understanding
Imagine a place in the cosmos far from all gravitational and
frictional influences. Suppose that you could visit that place and
throw a rock. The rock will a) gradually stop b) continue in motion
in the same direction at constant speed A 2-kg object is moving
horizontally with a speed of 4 m/s
A 2-kg object is moving horizontally with a speed of 4 m/s. How
much net force is required to keep the object moving at this speed
and in this direction? Mac and Tosh are arguing in the cafeteria.
Mac says that if he flings the Jell-O with a greater speed it will
have a greater inertia. Tosh argues that inertia does not depend
upon speed, but rather upon mass. Who do you agree with? Supposing
you were in space in a weightless environment, would it require a
force to set an object in motion? Fred spends most Sunday
afternoons at rest on the sofa, watching pro football games and
consuming large quantities of food. What affect (if any) does this
practice have upon his inertia? Explain. Ben Tooclose is being
chased through the woods by a bull moose that he was attempting to
photograph. The enormous mass of the bull moose is intimidating.
Yet, if Ben makes a zigzag pattern through the woods, he will be
able to use the large mass of the moose to his own advantage.
Explain this in terms of inertia and Newtons first law of motion.
Two bricks are resting on the edge of the lab table
Two bricks are resting on the edge of the lab table. Shirley
Sheshort stands on her toes and spots the two bricks. She acquires
an intense desire to know which of the two bricks is most massive.
Since Shirley is vertically challenged, she is unable to reach high
enough to lift the bricks, she can however reach high enough to
give the bricks a push. Discuss how the process of pushing the
bricks will allow Shirley to determine which of the two bricks is
most massive. What difference will Shirley observe and how can this
observation lead to the necessary conclusion? Answers B 0-NAn
object in motion will remain in motion unless acted upon by an
unbalanced force. Tosh. Inertia depends solely on mass. Yes! Even
in space, an object has mass which means it has inertia. A force
must be used to set an object in motion. If Fred continues this
habit, his mass will increase thus causing his inertia to increase.
The moose has a large mass which means it has a large inertia. This
large inertia requires more force to change the mooses state of
motion. The brick with the greater mass will have more resistance
to motion and will require a larger force to set into motion.
Newtons Second Law of Motion
According to Newton, an object will only accelerate if there is a
net or unbalanced force acting upon it. The presence of an
unbalanced force will accelerate an object changing its speed, its
direction, or both. Newtons second law of motion pertains to the
behavior of objects for which all existing forces are not balanced.
Newtons Second Law of Motion:The acceleration of an object as
produced by a net force is directly proportional to the magnitude
of the net force, in the same direction as the net force, and
inversely proportional to the mass of the object. a = Fnet m The
above equation is often rearranged to a more familiar form: Fnet =
ma As the force acting upon an object is increased, the
acceleration of the object is increased.
As the mass of an object is increased, the acceleration of the
object is decreased. The acceleration is directly proportional to
the net force; the net force equals mass times acceleration; the
acceleration is in the same direction as the net force; an
acceleration is produced by a net force. So, what am I trying to
get across? It is not just any ole force that is used in the
equation, it is the NET FORCE!
Reminder:The net force is the vector sum of all the forces acting
upon an object. Practice Net Force (N) Mass (kg) Acceleration
(m/s2) 10 2 20 4 5 The numerical information in the preceding table
demonstrates some important qualitative relationships between
force, mass, and acceleration. Comparing the values in rows 1 and
2, it can be seen that a doubling of the net force results in a
doubling of the acceleration (if mass is held constant). Comparing
the values in rows 2 and3, it can be seen that a doubling of the
mass results in a halving of the acceleration (if the force is held
constant). The direction of the net force is in the same direction
as the acceleration. Check Your Understanding
Determine the accelerations that result when a 12N net force is
applied to a 3 kg object then to a 6 kg object. A net force of 15N
is exerted on an encyclopedia to cause it to accelerate at a rate
of 5 m/s2. Determine the mass of the encyclopedia. Suppose that a
sled is accelerating at a rate of 2 m/s2. If the net force is
tripled and the mass is doubled, then what is the new acceleration
of the sled? Suppose that a sled is accelerating at a rate of 2
m/s2. If the net force is tripled and the mass is halved, then what
is the new acceleration of the sled? Answers 4 m/s2; 2 m/s2 3.0 kg
3 m/s2 12 m/s2 Motion Misconceptions
Sustaining motion requires a force. Two students are discussing
their physics homework prior to class. They are discussing an
object that is being acted upon by two individual forces (both in a
vertical direction); the free-body diagram for the particular
object is shown below. Fnorm = 20N Fgrav = 20N During the
discussion, Anna Litical suggests to Noah Formula that the object
under discussion could be moving. In fact, Anna suggests that if
friction and air resistance could be ignored, the object could be
moving in a horizontal direction. Noah objects, arguing that the
object could not have any horizontal motion if there are only
vertical forces acting upon it. Noah claims that the object must be
at rest, perhaps on a table or floor. After all, says Noah, an
object experiencing a balance of forces will be at rest. Who do you
agree with? Answer Annais correct. Noah Formula may know his
formulas but he does not know (or does not believe) Newton's laws.
If the forces acting on an object are balanced and the object is in
motion, then it will continue in motion with the same velocity.
Remember: forces do not cause motion. Forces cause accelerations.
Finding Acceleration Guided Practice
a = Fnet/m 1) An applied force of 50N is used to accelerate an
object to the right across a frictional surface. The object
encounters 10N of friction. Use the diagram to determine the normal
force, the mass, and the acceleration of the object. (Neglect air
resistance) Fnorm = _______ Ffrict =10N Fapp =50N Fgrav =80N An
applied force of 20N is used to accelerate an object to the right
across a frictional surface. The object encounters 10N of friction.
Use the diagram to determine the normal force, the net force, the
mass, and the acceleration of the object. (Neglect air resistance)
Fnorm = ________ Ffrict =10N Fapp =20N Fgrav =100N Guided Practice
Imagine you throw a baseball that weighs 0.1kg with a force of
100N. What is the acceleration of the baseball? An arrow leaves the
bow with a force of 500N. The mass of the arrow is 250kg. What is
its acceleration? A dog has a mass of 20kg. If the dog is pushed
across the ice with a force of 40N, what is its acceleration?
Graded Practice Suppose a student pushes a cart of groceries with a
40kg mass. How much force does he use if the cart accelerates 2.5
m/s2? A bag of charcoal has a mass of 10kg. Two bags were added to
the cart of groceries mentioned in problem 1. If the student pushes
with a force of 90N, what is the acceleration of the cart? If the
acceleration of the cart with the added mass of the two bags of
charcoal is increased to 2.5 m/s2, how much additional force must
be applied to the cart? Answers 100N 1.5 m/s2 60N Forces Practice
Worksheet 2 Answers 6000N 30N 5000N 2.5 m/s2 10 m/s2 2500 kg 20
m/s2 4N 50 m/s2 Formative Assessment 2 Weight and Second Law Math
Practice Net Force Practice Force Diagram Practice Worksheet
Terminal Velocity The free-body diagrams below show the forces
acting upon an 85-kg skydiver. As the skydiver falls, he picks up
speed. The increase in speed leads to an increase in the amount of
air resistance. Eventually the air resistance becomes large enough
to balance the force of gravity. At this instance, the net force
becomes 0N and the skydiver will quit accelerating.He has reached
terminal velocity. 700N 350N 833N 833N 833N 833N Newtons Third Law
of Motion
Newtons Third Law of Motion:For every action, there is an equal and
opposite reaction. Forces always come in pairs action-reaction. The
size of the forces are equal. The direction of the forces are
opposite. Examples of Interaction Force Pairs
Fish Swimming: A fish uses its fins to push water backwards as the
water pushes the fish forward. Birds Flying: The wings of the bird
push downward and the air is pushing the bird upwards. Car Moving:
As the wheels of the car spin, they grip the road and push the road
backward as the road pushes the car forward. Check Your
Understanding
For years, space travel was believed to be impossible because there
was nothing that rockets could push off of in space in order to
provide the propulsion necessary to accelerate. This inability of a
rocket to provide propulsion is because space is void of air so the
rockets have nothing to push off of. gravity is absent in space.
space is void of air and so there is no air resistance in space
nonsense!Rockets do accelerate in space and have been able to do so
for a long time. Many people are familiar with the fact that a
rifle recoils when fired
Many people are familiar with the fact that a rifle recoils when
fired. This recoil is the result of action-reaction force pairs. A
gunpowder explosion creates hot gases that expand outward allowing
the rifle to push forward on the bullet. Consistent with Newtons
Third Law of Motion, the bullet pushes backwards upon the rifle.
The acceleration of the recoiling rifle is greater than the
acceleration of the bullet. smaller than the acceleration of the
bullet. the same size as the acceleration of the bullet. In the top
picture, Kent Budgett is pulling upon a rope that is attached to a
wall. In the bottom picture, Kent is pulling upon a rope that is
attached to an elephant. In each case, the force scale reads 500N.
Kent is pulling with more force when the rope is attached to the
wall. with more force when the rope is attached to the elephant.
the same force in each case. Answers Answer:D It is a common
misconception that rockets are unable to accelerate in space. The
fact is that rockets do accelerate. There is indeed nothing for
rockets to push off of in space - at least nothing which is
external to the rocket. But that's no problem for rockets. Rockets
are able to accelerate due to the fact that they burn fuel and push
the exhaust gases in a direction opposite of the direction which
they wish to accelerate. Answer:B The force on the rifle equals the
force on the bullet. Yet, acceleration depends on both force and
mass. The bullet has a greater acceleration due to the fact that it
has a smaller mass. Remember: acceleration and mass are inversely
proportional. Answer:C Kent is pulling with 500 N of force in each
case. The rope transmits the force from Kent to the wall (or to the
elephant) and vice versa. Since the force of Kent pulling on the
wall and the wall pulling on Kent are action-reaction force pairs,
they must have equal magnitudes. Inanimate objects such as walls
can push and pull. Identifying Action-Reaction Forces
Identify at least six pairs of action-reaction pairs in the
following diagram. Answers The elephant's feet push backward on the
ground; the ground pushes forward on its feet. The right end of the
right rope pulls leftward on the elephant's body; its body pulls
rightward on the right end of the right rope. The left end of the
right rope pulls rightward on the man; the man pulls leftward on
the left end of the right rope. The right end of the left rope
pulls leftward on the man; the man pulls rightward on the right end
of the left rope. The tractor pulls leftward on the left end of the
left rope; the left end of the left rope pulls rightward on the
tractor. The tractors wheels push backward on the ground; the
ground pushes forward on the wheels. What Makes a Bug Go
Splat?
Splat! A bug has just flown into the windshield of an oncoming car.
The car must have hit the bug much harder than the bug hit the car,
right? Buzz:In order for the bug to fly through the air, a force
has to push the bug forward. Identify this force. How does the bug
produce it? (Hint. Think back to how a swimmer moves through the
water) Air pushes the bug forward.The bug produces this force by
pushing backward on the air with its wings, and the reaction force
is that the air pushes forward on the bug. The bug was at rest on a
tree when it saw the car and decided to fly toward it. If the bug
has a mass of 0.05 kg and accelerates at 2 m/s2, whats the net
force on the bug? 0.05 kg x 2 m/s2 = 0.1 N Vroom: The driver hates
killing bugs
Vroom:The driver hates killing bugs. When she saw one coming toward
the windshield, she braked suddenly and hoped it would get out of
the way. (Sadly, it did not.) When she hit the brakes, she felt
that she was thrown forward. Use one of Newtons laws to explain
why. Newtons first law says that objects in motion stay in
motion.The car stopped but she kept moving forward. Splat: The
unfortunate bug hits the windshield with a force of 1 N
Splat: The unfortunate bug hits the windshield with a force of 1 N.
If you call this the action force, what is the reaction force? Does
the car hit the bug any harder than the bug hits the car? Use one
of Newtons laws to explain why or why not. The windshield hits the
bug with a 1 N force.No; Newtons third law states that for every
force, there is an equal and opposite force. Compare the forces on
the bug and the car again
Compare the forces on the bug and the car again. Use another one of
Newtons laws to explain why the bug goes splat and the car keeps
going, without noticeably slowing down. Newtons second law;The same
force acts on both, but the bug has a much smaller mass, so it
accelerates much more. Newtons first law;The bug is not massive
enough to stop the car or change its motion. Assess Your
Understanding
A dog pulls on his leash with a 10 N force to the left, but doesnt
move.Identify the reaction force. The leash pulls on the dog with a
10 N force to the right. Using all three of Newtons laws, explain
how objects react to forces.
Sample:Newtons first law states objects change their motion when
force is applied.Newtons second law says the acceleration depends
on the strength of the force and the mass of the object.Newtons
third law says that whenever a force acts on an object, that object
applies an equal and opposite force back. Momentum The sports
announcer says, Going into the all-star break, the St. Louis
Cardinals have the momentum.The headlines declare St. Louis Rams
Gaining Momentum. The coach pumps up his team at half-time saying,
You have the momentum; the critical need it that you use that
momentum and bury them in the third quarter. Momentum is a commonly
used term in sports. A team that has the momentum is on the move
and is going to take some effort to stop. Momentum = mass
velocity
Momentum, however, is a physics term referring to the quantity of
motion that an object has. If an object is in motion, then it has
momentum. Momentum:mass in motion (vector quantity) Momentum is
dependent upon two things: how much stuff is moving (mass) and how
fast the stuff is moving (velocity). Momentum = mass velocity p =
mv Units:kg m/s An object at rest does not have momentum. 180kg x
16 m/s = 2880 kgm/s to the right
Guided Practice A lioness has a mass of 180 kg and a velocity of 16
m/s to the right. What is her momentum? 180kg x 16 m/s = 2880 kgm/s
to the right The warthog has a mass of 100 kg.What does the
warthogs speed have to be for it to have the same momentum as the
lioness? 28.8 m/s Graded Practice Find the momentum of the
following:
A 60 kg halfback is moving eastward at 9 m/s. A 1000 kg car is
moving northward at 20 m/s. A 40 kg freshman is moving southward at
2 m/s. A car possesses 20,000 units of momentum. What be the cars
new momentum if its velocity was doubled? its velocity was tripled?
its mass was doubled (by adding more passengers and a greater
load)? both its velocity and mass were doubled? A halfback (m= 60
kg), a tight end (m= 90 kg), and a lineman (m= 120 kg) are running
down the football field. Consider their ticker tape patterns below.
Compare the velocities of these three players. How many times
greater are the velocity of the halfback and the velocity of the
tight end than the velocity of the lineman? Which player has the
greatest momentum and why? Answers 1) a) 540 kgm/s b) 20,000 kgm/s
c) 80 kgm/s
d)80,000 kgm/s Tight End:covers twice the distance in the same
amount of time(v = 6 m/s) Halfback:covers three times the distance
in the same amount of time (v = 9 m/s) The tightend and the
halfback both have a momentum of 540 kgm/s, while the lineman only
has a momentum of 360 kgm/s Law of Conservation of Momentum
In the absence of an outside force (friction), the total momentum
of objects that interact does not change. The total momentum of any
group of objects remains the same, or is conserved, unless outside
forces act on the objects. Non-sticky Collisions
When two objects of the same mass (100 kg) collide and dont stick
together and outside forces are negligible, the objects trade
velocities.The car that is going faster before the collision will
end up slowing down, and the car that is going slower before the
collision will end up speeding up.Therefore, the momentums are the
same. Car 1: Car 2: m = 100 kg m = 100 kg v = 4 m/s v = 2 m/s M =
400 kgm/s M = 200 kgm/s Total M = 600 kgm/s After Collision: v = 2
m/s v = 4 m/s M = 200 kgm/s M = 400 kgm/s Sticky Collisions
Sometimes objects end up sticking together during a collision.Two
cars, which have the same mass, got tangled together after they
collided.Since one car was at rest and had a momentum of zero, only
the other car had any momentum before the collision.After they
collided and stuck together, the cars shared that momentum.The
total momentum of the two cars stayed the same. Check Your
Understanding
How can a heavy moving van have the same momentum as a small
motorcycle? Momentum equals mass times velocity, so the truck would
need to be moving more slowly than the motorcycle. What is the
momentum of a 750 kg car traveling at a velocity of 25 m/s? 750 kg
x 25 m/s = kgm/s The total momentum of two marbles before a
collision is 0. 06 kgm/s
The total momentum of two marbles before a collision is 0.06
kgm/s.No outside forces act on the marbles.What is the total
momentum of the marbles after the collision? 0.06 kgm/s Inertia v.
Momentum How are inertia and momentum related?
Inertia is the measure of how much resistance matter has to
acceleration. The more inertia something has, the less it wants to
respond to forces and accelerate. This statement is mathematically
stated a = F/m. (Newtons Second Law) The more force, the more
acceleration. The more inertia, the less acceleration. Momentum is
the product of inertia (m) and velocity (v).p=ma. The more inertia
something has, the more momentum it has, when in motion.
Predictions for the Year 3000