Download Stage 1 – Desired Results

Physics Case Study: Spare Me the Physics
Stage 1 – Desired Results
Content Standard(s):
Understanding (s)/goals
- Students will understand how the
basic physics of motion, forces,
energy and waves applies to the
sport of bowling
Essential Question(s):
- How can knowledge of physics be
used to improve a person’s bowling
game?
Student objectives (outcomes):
- Students will explain the motion, speed, velocity and acceleration of a bowling
ball as it moves down a lane
- Students will describe the forces involved in bowling
- Students will identify the forms of energy involved in bowling and explain how
energy is transformed
- Students will sense and explain the waves observed during bowling
Stage 2 – Assessment Evidence
Performance Task(s):
Other Evidence:
- Go bowling, observe and
record evidence of physics
(motion, energy, waves and
forces)
Stage 3 – Learning Plan
Learning Activities:
Engage: Story: Spare Me the Physics
Explore: Go Bowling!
Procedure: See questions
Debrief: See questions
Explain: Compare observations and answers to key
Evaluate: extend these concepts to explain how the same physics concepts
can be applied to bocce (lawn bowling)
Exit ticket: Answer essential question
Opening Narrative –
Case Study: Spare Me the Physics
Kenny came home from school, slammed his bookbag down in the corner, kicked his shoes off,
hurling them into the wall, slumped down into the couch and crossed his arms.
“Hi Kenny. What’s wrong?” asked Mary, Kenny’s mom.
“I didn’t make the bowling team” Kenny scowled.
“What did coach say?” inquired Mom.
“He said that there are some skills I need to improve before I can make JV. For now, I am stuck
on the freshmen team.” He pouted.
“When your older brother gets home today, let’s talk to him and see what pointers he can give
you.” Mary said, trying to console Kenny.
Later that day Kenny’s brother DeAndre came home. His mom told him what had happened so
DeAndre went up to Kenny’s room to talk to him.
“Hey bro..what’s happening?” asked DeAndre.
“Did mom tell you, I didn’t make the JV team. Coach said there are some things I need to work
on.” said Kenny.
“Well, it’s been a while since I’ve been to the bowling alley, but I think I still remember a thing or
two from my years on the Varsity team. What do you say we head to the lanes and try to work
on some things?” encouraged DeAndre.
“I guess so.” Replied Kenny
As they arrived at the lane DeAndre recommended to Kenny
“Let’s start by watching some of the other bowlers and analyze the different techniques. Once
we have watched them, we’ll get on a lane and begin experimenting with your shot. With a little
work, you might get pulled up to JV before you know it”.
As they watched the other bowlers, Kenny and DeAndre noticed a woman on the end lane that
was bowling really well. “Hey Kenny, I think that is my high school physics teacher, Mrs.
Robinson bowling down there. I had no idea she was such a good bowler.”
Just then, Mrs. Robinson glanced DeAndre and his brother out of the corner of her eye.
“Good to see you DeAndre. What are you up to these days?” inquired Mrs. Robsinson.
“Just finished my first year at College. I am here trying to help my younger brother work on his
game and make the JV bowling team.”
“Well we’re just about finished with this game. I could stick around and give you some help if
you like.” offered Mrs. Robinson.
“You do know that many of things we learned in physics class can help you with become a better
bowler, right?”Mrs. Robinson questioned DeAndre.
“I guess so, but I never really thought about it that way before Mrs. Robinson.” DeAndre
admitted.
“When you break it down, bowling is all based on motion, energy, forces and waves. Let me
show you how.”
Physics & the Sport of Bowling
Whether you have rolled a bowling ball or have never set foot in a local bowling
center you should be able to use the physical concepts we have been exploring and
observe with a careful scientific eye and describe the physics going on during a game.
We have talked about motion, forces, energy, heat, and waves. Whether you are
aware of them or not all of these physical phenomena can be observed during a simple
throw of a bowling ball down the lane.
A bit about bowling etiquette:








Always wear bowling shoes on the lanes.
Please do not cross the black foul line. The lane is oiled and the lane is very
slippery.
Wait for bowlers on the lanes to your right or left.
Be certain you wait until the pinsetting machine has completed its cycle and the
sweep bar is raised before rolling the ball.
Do not stray from your lane after delivering the ball.
Keep food and drinks in designated areas.
Try to keep your fun and games to within your own group.
Please clean up your area when finished and return balls to the rack.
Bowling & Physics Observations
Motion:
First let’s look at the motional part of bowling, specifically, the ball as it travels down
the lane. (We will worry about the pins later.) Throw a few balls down the lane and/or
watch others toss the ball down the lane. After you have witnessed the motion of the
ball, it is your job to try and answer the following questions.
1. Describe the shape(s) of the path of a ball down the lane. Is the motion straight
or curved?
2. A bowling lane is 60 feet long, use a stopwatch, to determine the average speed
down the lane of a tossed bowling ball.
3. Does everyone throw a ball at the same average speed?
4. What is happening to the “speed” of the ball down the lane once it is thrown?
Any idea why?
5. What is happening to the “velocity” of the ball down the lane once it is thrown?
Any idea why?
6. Does the ball experience “acceleration” once the ball is thrown down the lane?
Why of why not?
Motion Diagrams:
1. Let’s try and draw a vector diagram of the motion of a bowling ball down the
lane. Using the diagram, add your own observations of the ball at various times
down the lane. (For example, you can time the ball from the moment it is
thrown. Say, it takes 4 seconds for the ball to reach the pins – you could draw
an approximation of where you feel the ball is on the lane at 0s, 1s, 2s, 3s, and
4s.)
2. To the diagram - add an indication (arrows) of the velocity of the ball at those
times.
3. To the diagram - add an indication (arrows) of the acceleration you feel the ball
is experiencing down the lane.
Side View
Overhead View
Forces:
Now we can begin to ask ourselves questions about why the bowling ball is moving
in the ways that we have observed. Let’s try and answer these questions concerning the
forces that are in action during the motion of the bowling ball and its interaction with
the bowling pins.
1. What “force(s)” are acting on the ball to get it in motion down the lane? (There
might be many possible answers for this.)
2. Once the ball is rolling down the lane, is there still a force(s) acting on the ball?
3. What do these forces acting on the ball cause the ball to do in terms of motion?
4. Once the ball is rolling down the lane, what is the direction of the force(s)?
(Think carefully – conceptual pitfall)
5. How does the “mass” of a ball change the action of the forces?
6. Before the ball “hits” the pins, what is the speed of the pins?
7. Does the ball “hitting” the pins cause the pins to experience a change in velocity?
8. Do the pins experience a force when the ball “hits” them? How do you know?
Energy:
Energy is everywhere - we just have to identify the forms of energy and when and
how it transfers between energy types.
1. Does the rolling bowling ball have “energy?” If so, what kind of energy?
2. Where did the energy the ball has moving down the lane come from? What is
this type of energy?
3. Does every throw of a bowling ball have the same energy? Why or why not?
4. Do the pins have any easily observable kinetic energy before the ball hits them?
Why or why not?
5. After the ball hits the pins, do the pins have any kinetic energy? How do you
know?
6. If we compared the total amount energy of the bowling ball before it hits the
pins to the total amount of energy of the pins and ball after it hits the pins what
would we find? Upon what principle do you base your conclusion?
7. Can you identify any time during the motion of the bowling ball down the lane
and/or when it hits the pins where we might say the “heat and/or temperature”
of an object changed? (Hint: think friction and/or kinetic energy.)
Waves:
The periodic motion of waves is also going on during the game. In fact, it is being
sensed by a way we observe the game as it happens.
1. Do you hear anything during a throw of the ball down the lane? What?
2. Do you hear anything during the collision between the ball and pins? What?
3. Explain, how you can “hear” these events? Does it have anything to do with
waves?
4. Does it take “energy” to hear these “sounds?” Why or why not?
5. Where does this energy come from?
Conceptual Summary
Simply, the concepts and physical phenomena that science (physics) tries to explain are
going on around us all the time. In a simple game of bowling, we can witness all types of
situations that deal with motion, speed, velocity, acceleration, vectors, forces, kinetic and
potential energy, conservation of energy, heat, and waves. I hope this little activity, can help
inspire in you a new way to look at every day life and “see” the physics behind the observations.
Science is going on all around us and we certainly use it pragmatically everyday (sometimes in a
formal mathematical way) just living our lives.
Physics & the Sport of Bowling
Whether you have rolled a bowling ball or have never set foot in a local bowling
center you should be able to use the physical concepts we have been exploring and
observe with a careful scientific eye and describe the physics going on during a game.
We have talked about motion, forces, energy, heat, and waves. Whether you are
aware of them or not all of these physical phenomena can be observed during a simple
throw of a bowling ball down the lane.
A bit about bowling etiquette:








Always wear bowling shoes on the lanes.
Please do not cross the black foul line. The lane is oiled and the lane is very
slippery.
Wait for bowlers on the lanes to your right or left.
Be certain you wait until the pinsetting machine has completed its cycle and the
sweep bar is raised before rolling the ball.
Do not stray from your lane after delivering the ball.
Keep food and drinks in designated areas.
Try to keep your fun and games to within your own group.
Please clean up your area when finished and return balls to the rack.
Bowling & Physics Observations
Motion:
First let’s look at the motional part of bowling, specifically, the ball as it travels down
the lane. (We will worry about the pins later.) Throw a few balls down the lane and/or
watch others toss the ball down the lane. After you have witnessed the motion of the
ball, it is your job to try and answer the following questions.
7. Describe the shape(s) of the path of a ball down the lane. Is the motion straight
or curved?
Some people will have a straight path, others a hook or curved
path depending on how they throw the ball.
8. A bowling lane is 60 feet long, use a stopwatch, to determine the average speed
down the lane of a tossed bowling ball.
Average Speed=distance/time = 60 ft / 2.5 seconds = 24 ft/s. (
About 18 mph – answers will vary for each person)
9. Does everyone throw a ball at the same average speed?
No. Some throw the ball with a higher average speed, others
slower.
10. What is happening to the “speed” of the ball down the lane once it is thrown?
Any idea why?
The speed appears to be decreasing as the ball travels down the
lane. The force of friction will help to slow the ball because it
always opposes motion.
11. What is happening to the “velocity” of the ball down the lane once it is thrown?
Any idea why?
Ah! Many descriptions are possible. The ball’s speed is decreasing
therefore the velocity is also decreasing. In addition, if the ball
has a curved path down the lane the direction the ball is traveling
is also changing. So, the direction and speed may both be
changing!
12. Does the ball experience “acceleration” once the ball is thrown down the lane?
Why of why not?
Yes, any change in velocity is the definition of acceleration.
Motion Diagrams:
4. Let’s try and draw a vector diagram of the motion of a bowling ball down the
lane. Using the diagram, add your own observations of the ball at various times
down the lane. (For example, you can time the ball from the moment it is
thrown. Say, it takes 4 seconds for the ball to reach the pins – you could draw
an approximation of where you feel the ball is on the lane at 0s, 1s, 2s, 3s, and
4s.) (I did the picture below for a straight throw)
5. To the diagram - add an indication (arrows) of the velocity of the ball at those
times. (Velocity vectors are solid arrows)
6. To the diagram - add an indication (arrows) of the acceleration you feel the ball
is experiencing down the lane. (Acceleration vectors are dashed)
Side View
Overhead View
Forces:
Now we can begin to ask ourselves questions about why the bowling ball is moving
in the ways that we have observed. Let’s try and answer these questions concerning the
forces that are in action during the motion of the bowling ball and its interaction with
the bowling pins.
9. What “force(s)” are acting on the ball to get it in motion down the lane? (There
might be many possible answers for this.)
Many good answers are possible. Force of gravity (or weight of
the ball), forces applied by the muscles in the bowler’s arm, forces
applied by the fingers to impart spin in the ball, muscles in the
bowler’s legs to accelerate the ball (and bowler) forward…etc……
10. Once the ball is rolling down the lane, is there still a force(s) acting on the ball?
Sure, some are in balance with other forces ( for example force of
gravity downward into the ground toward the Earth’s center and
the upward force the lane surface provides – normal force) and
others are not. Friction is unbalanced by any other force,
therefore the ball experiences an acceleration – “slowing down.”
(Friction is the “net Force” causing the ball to slow down)
11. What do these forces acting on the ball cause the ball to do in terms of motion?
If there is a “net Force” (such as friction in this case) the ball
experiences an acceleration making the ball “slow down.”
12. Once the ball is rolling down the lane, what is the direction of the force(s)?
(Think carefully – conceptual pitfall)
Since the ball is “slowing down” and a “net Force causes masses
to accelerate” – then the acceleration (and therefore frictional
force) of the ball is in the opposite direction as
velocity
friction
the velocity of the ball.
13. How does the “mass” of a ball change the action of the forces?
The larger the mass, the harder it is for the “forces” to cause a
change in the motion (larger mass – smaller acceleration with a
given force).
14. Before the ball “hits” the pins, what is the speed of the pins?
They are not moving – zero. (They may have been wobbling a bit,
but mostly not moving)
15. Does the ball “hitting” the pins cause the pins to experience a change in velocity?
Yes, they are moving with many different speeds in many
different directions after the ball hits them. So they were mostly
stationary before the ball hits and moving after.
16. Do the pins experience a force when the ball “hits” them? How do you know?
Yes. Each pin is a mass. Each pin experienced a change in velocity
which we call “acceleration.” When a mass accelerates we say it
has experienced a “net force!”
Energy:
Energy is everywhere - we just have to identify the forms of energy and when and
how it transfers between energy types.
8. Does the rolling bowling ball have “energy?” If so, what kind of energy?
Yes, kinetic energy of motion.
9. Where did the energy the ball has moving down the lane come from? What is
this type of energy?
Bowlers “raise” the ball upward above the lane before throwing it.
This increases the ball’s gravitational potential energy. The bowler
then drops it into a swing and lowers it to the lane surface
converting the potential energy of position to kinetic energy of
motion. (Some bowlers will also add some energy by using the
muscles of the arm and legs as well…… )
10. Does every throw of a bowling ball have the same energy? Why or why not?
No, a faster ball will have more kinetic energy than a slower ball
traveling down the lane.
11. Do the pins have any easily observable kinetic energy before the ball hits them?
Why or why not?
No, the pins are stationary. No motion – no kinetic energy. (Why
did I say “easily observable?” – Well, the pins do have a
temperature – the nanoscale particles that make up the solid
wood of the pins will be jiggling with some motion.)
12. After the ball hits the pins, do the pins have any kinetic energy? How do you
know?
Yes, clearly the pins are moving around after the bowling ball hits
them. Moving pins means they have kinetic energy that is easy to
see.
13. If we compared the total amount energy of the bowling ball before it hits the
pins to the total amount of energy of the pins and ball after it hits the pins what
would we find? Upon what principle do you base your conclusion?
The total amount of energy before the ball hits the pins will be
equal to the total amount of energy after the collision. We just
need to be careful to identify all the energy amounts and types
before and after the collision. (….energy of the ball before and
after, energy types of the pins before and after, energy in the
“sound” waves the collision creates…etc…). This is the Law of
Conservation of Energy.
14. Can you identify any time during the motion of the bowling ball down the lane
and/or when it hits the pins where we might say the “heat and/or temperature”
of an object changed? (Hint: think friction and/or kinetic energy.)
Temperature is based on the “average kinetic energy” of all the
pieces (molecules, atoms, etc) in a substance. So, in a sense,
anytime there is a “change in the kinetic energy” of something
you are “changing the temperature.” The pins have a “change in
kinetic energy.” The pins are not moving around much before the
collision, but after they are moving around a lot more. The pins as
a collection of particles could be said to have experienced a
temperature change.
Waves:
The periodic motion of waves is also going on during the game. In fact, it is being
sensed by a way we observe the game as it happens.
6. Do you hear anything during a throw of the ball down the lane? What?
“Thunk” of the ball hitting the alley. “Rumble” of the ball rolling on
the lane….…. “Hip-Hip-Hooray” of the bowler celebrating a strike!
7. Do you hear anything during the collision between the ball and pins? What?
“KaaPow” of the ball hitting the pins. “Crash” of the pins hitting
each other.
I observe “sounds.”
8. Explain, how you can “hear” these events? Does it have anything to do with
waves?
Some of the energy during the bowling ball’s collision with the
pins is transferred to air molecules near the collision causing them
to vibrate. This disturbance in the air molecules travels outward as
a longitudinal sound wave to the bowler’s ears so that she “hears”
the sound of the “KaaPow.”
9. Does it take “energy” to hear these “sounds?” Why or why not?
Yes, vibrations, oscillations, waves, depend on something moving
– therefore kinetic energy of motion is involved in the process.
10. Where does this energy come from?
Somewhere else. (Not trying to be coy). Energy is neither created
nor destroyed, so any energy comes from somewhere else by
changing form or being transferred from place to place and
process to process. The energy in question creating the sound
came from the kinetic energy of the ball which came from the
potential energy the bowler gave the ball by lifting it, but the
bowler ate some food earlier in the day to store energy to lift the
ball, the food eaten got the energy from………… this list goes
forever……
Conceptual Summary
Simply, the concepts and physical phenomena that science (physics) tries to explain are
going on around us all the time. In a simple game of bowling, we can witness all types of
situations that deal with motion, speed, velocity, acceleration, vectors, forces, kinetic and
potential energy, conservation of energy, heat, and waves. I hope this little activity, can help
inspire in you a new way to look at every day life and “see” the physics behind the observations.
Science is going on all around us and we certainly use it pragmatically everyday (sometimes in a
formal mathematical way) just living our lives.