Find The Change In Mass Of Each Marble In Time And Distance T ?

2.3.1.2. Lesson plan number 1

CHAPTER IV: LAWS OF CONSERVATION

Lesson 37: MOMENTUM - LAW OF CONSERVATION OF MOMENTUM

I. Objectives

1. About knowledge.

(Lesson 1)

- State the definition of momentum, state the nature and unit of measurement of momentum. State the consequence: a force with sufficient intensity acts on an object.

in a short period of time can cause the momentum of an object to change.

- Deduce the expression of the momentum change theorem

(p  Ft)

definition

Newton's second law

(F  ma)

2. About skills.

- Apply the second way of writing Newton's second law to solve related exercises.

3. Attitude, feelings.

- Form an enthusiastic and passionate attitude towards learning.

- Be proactive in learning.

- Take the initiative to express your opinion.

II. Lesson preparation.

1. Teacher.

- Teaching aids and tools.

- Study cards:

STUDY SHEET NO. 1

Class .............................. Group..........................................

* Review

+ Player A volleyed the ball into the opponent's net.

+ The billiard ball is moving fast, touching the edge of the table and changing direction.

for example:

STUDY SHEET NO. 2

Class .............................. Group..........................................

An object of mass m, is moving

a force F of magnitude



crowded with speed

v . Effect

put on the object

v .

If the velocity of the object does not change in time t, then the velocity of the object will be constant.

+ Find the family tree of

obtained object.



etc.

 

2.Students.

Review Newton's laws, closed systems, momentum.

Expected scoreboard

CHAPTER IV: LAWS OF CONSERVATION

Lesson 37: MOMENTUM - LAW OF CONSERVATION OF MOMENTUM

I. MOMENTUM.

1. Impulse of force.

(Lesson 1)



- When a force  acts on a

space object



time t



then the product F t is

defined as the impulse of force F in time interval

space

that

- The unit of impulse of force is: Newton second (KH: Ns)

2. Dong Luong

* Define:

The mass of an object of mass m is moving

crowded

Cloud

I am

quantity determined by the formula:

p  mv

- Unit: kilogram.meter per second (kg.m/s)

- We have:

p  p  p  mv  mv  Ft p  Ft

2 1 2 1

* .Momentum change theorem (another expression of Newton's second law):

amplitude

crab abundance

one

thing

in one

space

any time

crab tape

cardboard

force

impact

put on object

in space

measurement time

The change in momentum is calculated by the formula:

p  p  p   t

2 1 F

* Meaning: A sufficiently strong force acting on an object for a finite period of time can cause a change in momentum.

III. Teaching process.

1. Stabilize the class.

2. New post.

Activity 1 (5 minutes): Review old lesson

1. Review the expression of Newton's second law?

2. State and write the expression of Newton's third law?

Activity 2 ( 35 minutes): Learn the concepts of force impulse and mass .

Question : When a force acts on an object , it causes the object's state of motion to change . Which quantity characterizes the changed state of motion of the object ?

We will have the answer when we study this lesson.

Student activities

Help teachers

Students pay attention to the old knowledge they have learned.

miss

again

the

ants

Teacher:- Brief introduction about the birth

life and meaning of conservation law.

- Introduce the basic conservation laws of mechanics.

* Learn about the momentum of force.

Teacher:Distribute study sheet number 1.

content:

* Consider the examples:

+ Player A volleyed the ball into the opponent's net.

+ The billiard ball is moving

move fast, touch the table

Maybe you are interested!

HS: Divide into groups according to the assignment of change of direction.

HS: think and answer the question

Good

let me know

time of action

content

force and magnitude

of force

content?

Students answer the question:

- The force acting time is very short.

- The magnitude of the force applied is significant.

* Teacher's suggestion

+ How long does the force act on the ball?

+ The magnitude of the force acting like that

any ?

- can be considered force time

 effect

+ Teacher: Maybe

watch

 remains constant

into the object is very short t

in short time  t or not?

* Teacher asks students to read part 1b of the textbook and answer the questions:

+What is the impulse of the force?

- When one

force  acting on a

object

in time interval t then product  t

F 

is defined as the impulse of the force

 in time interval t

that

* Problem statement

concept formation

Students think and identify research problems.

need

Momentum concept:

When a force acts on an object, it causes the object's state of motion to change.

+ Which quantity characterizes the state of motion of a changed object?

+ Find the relationship between the momentum of the force and the mass and velocities of the object?

* Problem solving.

GV: Correct:

study card number

2. Cradle

An object with mass m is

specialized

crowded

speed

v . Effect

exert force on an object

 has a large magnitude

not double

in time

time t

exam

speed

crab

thing

land

v .

+ Find family

crab

obtained

+ Calculate the momentum of force  according to v

HS: discuss and give answers.

F 1

; v and m

- The acceleration of the object obtained is:

Teacher suggests: What is the formula for a?



 v  v

How does a relate to F?

a 2 1

t

- Impulse of force

 according to v ; v and m

has the form:

mv

 mv

F 1 2



 Ft

Teacher:Comment on students' answers and make announcements:

+ The right side is the impulse of the force

effect

+ The left side is the variation of the quantity.

quantity

p  mv

and p is called

momentum of the object.

Student answer:

- Frozen crab

one

thing

strong

So the mass of an object is the belt.

how much? what is the unit?

v is a quantity determined by the formula: p  mv

- Unit: kilogram.meter per second (kg.m/s)

- The momentum change is calculated by the formula:

p  p  p   t

2 1 F

- The change in momentum of an object in a certain time interval is equal to the impulse of the sum of the forces acting on the object in that time interval.

HS: Complete C1, C2:

- C1: due to kgm / s  kgms with kgm  N

s2 s2

Teacher:Student presentation comments and

conclude.

- Return to exercise 2. requirements

or find the amplitude of mass?

* Hint: Let p be the variation

momentum

- So between the east and west ranges

amount of object in space

time t and impulse of the force

time capsule

how is that related

Teacher:Introduce the above statement

be seen as a way of expressing

different from Newton's second law. Meaning

Meaning: A strong enough force acting on

an object in a period of time

finite time can cause

momentum change

Teacher:Requires thought and completion

into questions C1, C2 in

mass moving with velocity

Therefore:

kgm / s  kgms  Ns

s 2

- C2: mv  mv   t with

F

v0  0  mv  Ft

 v  Ft  5m / sm

Textbook

Activity 3 (5 minutes ) : Consolidation, application

- Ask questions and give homework.

- Ask students to prepare for the next lesson.

IV. TEACHING EXPERIENCES.

2.3.1.3. Lesson plan number 2.

CHAPTER IV: LAWS OF CONSERVATION

Lesson 38: MOMENTUM - LAW OF CONSERVATION OF MOMENTUM

I. Objectives

1. About knowledge.

- Isolated system, the system is considered isolated.

- Content and expression of the law of conservation of momentum.

2. About skills.

(Lesson 2)

- Apply the law of conservation of momentum to solve related exercises.

- Explain the principle of jet motion.

3. Attitude, feelings.

- Form an enthusiastic and passionate attitude towards learning.

- Be proactive in learning.

- Take the initiative to express your opinion.

II. Lesson preparation.

1. Teacher.

- Study cards.

STUDY SHEET NO. 1

Class .............................. Group..........................................

On a completely horizontal plane

There are 2 marbles rolling.

collision

into each other.

1 Find the change in momentum of each marble in time interval t?

2 Compare the momentum variation of the two marbles?

3 Compare the total momentum of the system before and after the collision?

STUDY SHEET NO. 2

Class .............................. Group..........................................

An object with mass m1 moves on a smooth horizontal plane with

velocity v collides with an object of mass m standing still on a flat surface



horizontal. Knowing that after the collision, the two objects merge into one, moving with the same velocity v. Determine v?