1. Lesson T emplate
Name of the teacher : Deepa N Bhadran Std : 9
Name of the school : St. John's HSS Undancode Stre: 54/55
Subject : Physics
Unit : Gravitation Date: 10/07/14
Topic : Gravitational force on a body depends on its mass Duration: 45 min
Curicular Statement
Pupil are made aware of the concept of gravitational force through experiment, observation, discussion and tabulation of facts.
Content Analysis
Terms : spring balance, gravitational force
Facts :
1. The earth attracts all objects towards its earth.
2. The gravitational force is different in different objects.
3. Ripe mangoes from a tree , a stone hurled in to the air, rain drops, all fall to the earth.
4. Any object whose path is not hindered falls to the earth.
2. 5. Spring balance is used to find the weight of the body.
6. Force is needed to elongate a spring.
7. When the quantity of matter increases, the mass also increases.
8. Bottle full of water has greater mass than a bottle half filled with water.
9. The earth exerts greater force on a coconut than an apple.
10. The gravitational force is greater to an elephant than a goat.
Concept :
The earch attracts all things towards its centre. This is called gravity. The force experienced by a body owing to gravity is called gravitational
force. The gravitational force of the earth on a body depends on the mass of the object and distance between two objects.
Learning outcome
Remember : Pupil will recall, list out and identify the term gravitational force.
Understanding : Pupil will explain, compare and summarise the factors influencing the gravitational force.
Apply : Pupil will apply the coneptual and factual knowledge of attractive force between the objects in their daily life.
Analyse : Pupil will analyse the importance of gravitational force in various experiments.
Evaluate : Pupil will formulate a judjument based on the factors influencing the gravitational force.
Create : Pupil will create a model of spring balance.
Pre-requisites : Pupil already know that objects fell down and the earth attracts all objects towards it.
Teaching – learning resource : Text book , hand book, spring balance, bottle, water,etc.
Formative evaluation procedure : questions, discussion and model preparation.
3. Class room interaction procedure Response
Posing the problem :
Teacher presents a situation to the class. While Sonu was sitting on the terrace reading his lessons, a breeze
flew off the papers. Along with the paper his pen also fell down. But the pen touched the ground first. Sonu wondered.
Teacher asks the students to discuss the following questions.
Discussion points :
➢ Why the papers and the pen fell down?
➢ Whether it was the greater mass of the pen that made it fall faster, what do you think?
Consolidation :
The papers and the pen fell down due to the attractive force of the earth. The slow speed of the paper is due
to the difference in resistance of air. The force depends on the mass of the object. The earth attracts all objects
towards its centre. Today we are going to discuss about this gravitational force.
Teacher divides the pupil into different groups.
Activity 1 :
Teacher hangs a spring balance and pulls its hook downwards. Then teacher asks the students to find out
answers of the following through discussion and observation.
Discussion points :
♦ Haven't you seen that the reading in the balance has changed?
♦ What caused the change in the reading in the spring balance?
♦ When does the change in the reading become greater?
Consolidation :
The reading in the balance has changed. The change in the reading is due to the force applied on the hook
Expected Actual
Pupils are
listening.
Pupils are
discussing.
Pupils are
listening.
Pupils divide in
to groups.
Pupils are
observing.
Pupils are
discussing.
Pupils are
listening.
4. of the spring balance. When greater force acts on the hook of the spring balance the reading becomes greater.
Activity 2 :
Teacher tolds the students to hang an object from the hookof the spring balance. Teacher asks the pupil to
write down their observation.
Discussion points :
♦ Why did the spring get extended when the object was hung from it?
♦ Haven't you find out a factor that influences the gravitational force?
♦ Does the gravitational force of the earth on a body depend on the mass of the body alone?
Consolidation :
The spring get extended due to the attractive force of the earth acting on the object. Earth exerts a force on
suspended objects. The earth attracts all the thingstowards its centre. This is called gravity. The force experienced by
a body owing to gravity is called gravitational force.
Activity 3 :
Teacher tolds the pupil to hang a bottle half filled with water at the hook of a spring balance. Then fill the bottle
with water and hang it again. Then she tolds to write down the readings in a table and discuss the following
questions.
Discussion points :
Sl
Object hung from the spring balance Reading
No.
1 Bottle half filled with water
2 Bottle full of water
♦ Don't you know that when the quantity of matter increases, the mass also increases. If so, which one of the
objects given in the table is of greater mass?
Pupils do the
experiment.
Pupils are
discussing.
Pupils are
listening.
Pupils doing the
experiment.
Pupils are
discussing.
Pupils are
listening.
5. ♦ Which one is attracted towards the earth with greater force?
♦ Haven't you found out a factor that influences the gravitational force?
♦ Does the gravitational force of the earth on a body depend on the mass of the body alone?
Consolidation :
Bottle full of water has greater mass and it is attracted towards the earth with greater force. A factor that influence
the gravitational force between the earth and an object is its mass. The gravitational force of the earth on a body also
depends on the distance between the object and the earth.
Closure:
Teacher asks the following questions,
1. Does the earth exert greater force
a) on an apple or on a coconut?
6. b) on an elephant or on a goat?
Review and follow up activity :
I. 1).What do you mean by gravitational force?
2) What are the factors influencing the gravitational force between the earth and the object?
II. Find out the situations from your daily life that you experience the gravitational force.
7. b) on an elephant or on a goat?
Review and follow up activity :
I. 1).What do you mean by gravitational force?
2) What are the factors influencing the gravitational force between the earth and the object?
II. Find out the situations from your daily life that you experience the gravitational force.
