Transcript Gautam - Assignment - BBSR

WORKSHOP PRESENTATION
Gautam Bhattacharya
Faculty, SCERT (WB)
LESSON PLAN
SUBJECT: SCIENCE
GRADE: SEVEN
TOPIC: NEWTON’S
THIRD LAW OF
MOTION
DURATION: APPROXIMATELY
30 MINUTES
TEACHING POINTS
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Concept of force
Concept of action
Concept of reaction
Concept of Action-Reaction pair
Relation between Action & Reaction
Mathematical formulation
Law governing Action & Reaction
LEARNING OBJECTIVES
• List out types of forces seen around in every
day life
• Define force, action and reaction
• Identify the pairs of Action-Reaction forces
• Cite real life examples Action and Reaction
• Describe the process involved in a real life
situation where Action-Reaction pair is involved
LEARNING OBJECTIVES (…cond)
• Distinguish the forces in terms of Action
and Reaction
• Establish the relationship between Action
& Reaction
• Enunciate Newton’s Third Law of Motion
• Apply the concept of the NTLM in real life
situations.
ICT TOOLS REQUIRED
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World wide web (internet navigation)
Wikis / Blogs
Video clips
You-tubes
Digital portfolios
Constructivist strategies employed for teaching
• observe surroundings for points of curiosity
• ask questions
• consider possible responses to questions
• note unexpected phenomena
• identify situations where student perceptions vary
• exploration
• engage in focused activity
Constructivist strategies for teaching (…contd.)
• brainstorm possible alternatives
• design a model
• look for information
• evaluate choices
• experiment with materials
• engage in debate
• observe specific phenomena
• analyze data
Constructivist strategies for teaching (…contd.)
• employ problem-solving strategies
• collect and organize data
• select appropriate resources
• discuss solutions with others
• design and conduct experiments
• propose explanation and solutions
• construct and explain a model
• utilize peer evaluation
Observe surroundings for points of curiosity
• View the online video clip from:
www.youtube.com/watch?v=mNM5tHou4IQ
• Watch this NASA video segment from:
www.nasa.gov/audience/.../The_Law_of_Action_an
d_Reaction.html
Questions to Students:
• While driving down the road, a fly strikes the
windshield of a bus - the fly hit the bus and
the bus hits the fly. Which of the two forces is
greater: the force on the fly or the force on
the bus?
Questions to Students (…contd):
• 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
Newton's third law of motion, the bullet pushes backwards
upon the rifle. The acceleration of the recoiling rifle is ...
a. greater than the acceleration of the bullet.
b. smaller than the acceleration of the bullet.
c. the same as of the bullet.
Questions to Students (…contd):
• In the top picture, shown above, a man is pulling a rope that is
fixed to a wall. In the bottom picture, the man is pulling upon a
rope the other end of which is tied to an elephant. In each
case, the force scale reads 500 Newton. The man is pulling ...
a. with more force when the rope is attached to the wall.
b. with more force when the rope is attached to the elephant.
c. the same force in each case.
OBSERVATIONS BY STUDENTS - I
• Force is an external agent which changes or tends to
change the state of rest or of uniform motion of a
body in a straight line.
• In nature forces occur in pair.
• The pairs of forces are formed by Actions and
Reactions.
• In nature there are several examples of Actions and
Reactions.
FURTHER EXPLORATION BY STUDENTS
Can we consider any couplet of forces as ActionReaction pair? Consider the following:
A horse is pulling a carriage on a level ground. The horse
knows the third law of motion. The horse will exert a force
forward, and the carriage will exert a force equal to the horse's
force but in opposite directions. Therefore, the horse can never
pull the carriage forward!
Can you explain how is then the carriage pulled forward?
Visit the following site for a possible suggestion:
http://www.grc.nasa.gov/WWW/k12/WindTunnel/Activities/third_law_motion.html
OBSERVATIONS BY STUDENTS - II
• Not any couplet of forces may be termed
as Action-Reaction pair.
• Isolated body is to be considered for
identifying the all the forces acting on it.
• Only the unbalanced force causes
acceleration in a body.
EXPLORATION BY STUDENTS
• Virtual trip to science gallery to observe
Action-Reaction pair and Acceleration
under Unbalanced Force from PBL site of
Clarkson University:
www.clarkson.edu/k12
• See the Video on:
http://www.khanacademy.org/video/newtons-third-law-of-motion?playlist=Physics
Collection & Organisation of Data
• The students will prepare a write up in
www.edublog.org on occurrence of ActionReaction pair in nature and occurrence of
motion under unbalanced force.
Proposing a Relationship
• Action and Reaction are equal in
magnitude but opposite in direction.
In other words,
“To every Action there is an equal
and opposite Reaction.”
- Statement of Newton’s 3rd Law of Motion
Construct and Explain a Model
• Follow the link below to construct meaning
out of the situations described therein:
http://www.khanacademy.org/video/newton-sthird-law-of-motion?playlist=Physics
EVALUATION
• Visit the following site to see Interactive
Simulation on 1-D Motion and solve the
problems provided therein:
http://phet.colorado.edu/en/contributions/vie
w/3423
• Teacher/Peer/Self evaluation of learner through
some of the ICT tools that assist in this
diagnostic process like:
e- portfolio, digital mapping, assignment etc.
THANK YOU…
…for your kind audience