skenario englis efek doppler sin

7/29/2019 SKENARIO ENGLIS Efek Doppler Sin

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LEARNING SCENARIOS

Teacher : Morning, student. (Giving a friendly condition in learning process).

Student : Morning, Miss.

Teacher : How are you? (Giving a friendly condition in learning process).

Student : Fine, Miss.

Teacher : Nice to meet all of you in healthy conditions. Well, before we start our

lesson today, let us pray together. Pray began. (Students and teachers pray

together). Pray its over. Okay student, now at the first I will continue to

checking your absent. Anyone absent today? (Giving a friendly condition in

learning process).

Student : No, Miss.

Teacher : All of you my diligent student, right. Now we will learn about the Doppler

effect. Indicator of this learning are you be able to explain the definition of

Doppler effect, knowing the phenomenon of Doppler effect, understanding the

formula and applied it to solve some problem of Doppler effect. But before we

start this lesson, are you guys ready for the lesson today? (concentration)

Student : Yes, Miss.

Teacher : Thats great, it means youve learned the chapter to this meeting. Okay

student, I want to ask you, have you seen the ambulance car and police patroly

car in the road? (Question of trackers and deployment).

Student : Im, Miss. At that time I was sitting in a shop near the road, there is

ambulance with its sirens fast moving.

Teacher : Good opinion. Another opinion again? (Giving an opportunity to answer

for the other student).

Student : Im, Miss. When I was riding a bike. I was heared an ambulance sirene from

behind me. When the ambulance moving near to me, then siren voice even

louder. But, when the car is far away of me, then siren sounds is smaller.

Teacher : Interesting experiences. Another opinion again? (Deployment, giving an

opportunity to answer for the other student).

Student : Im, Miss. At that time there was a police car parked complete with siren

voice from across the way. When I was a distance away by car, I heard the

sirens sound small. However, when the distance to the car I got closer, the

sound of sirens gradually loudly.

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Teacher : Good. Well, there are the third opinion of your friends. Let's give applause

to your friends! To understand more clearly about the events of the Doppler

effect, let's do a demonstration of the Doppler effect. Here, I was preparing a

sound source that made from the battery that connected with beser. Before

starting, whos can help me to doing this demonstration? I need 2 volunteers.

(Preparation implementation of demonstration)

Student : Two students, raised his hand.

Teacher : All right. You two please come forward. Now, Adi please hold the sound

source and please sit in this position. Later, Ivan please stand at the end of the

exit. After I instructed to get in, please Ivan walked toward the sound source.

Already guys? (Concentration).

Student : Yes, Miss.

Teacher : Come on, now Ivan entered and approached the sound source. (Giving a

clear instruction)

Student : Student was walked approaching sound source.

Teacher : What you hear after doing the demonstrations, guys? (Analytical question,

asking a relevant answers).

Student : When I was at the end of the door, I heard the sound source is smaller, Miss.

But when I started to move closer to the source of sound, I heard more

clearly.

Teacher : Good. Now, I wants to ask Adi, did you hear the difference frequency of the

sound source as described by Ivan earlier? (Analytical question, asking a

relevant answers).

Student : No, Miss.There is no change of frequency that I heard.

Teacher : Good job. Anyone can help me to related the Doppler effect with a second

opinion that said by your friend before? (Understanding question, asking a

relevant answers).

Student : Im Miss. Doppler effect is related to the distance of the weak sound loud

that we hear depends on the distance of the listener and the sound source.

Teacher : Well, guys. Your answer is not wrong, but it needs to be completed further.

Let anyone who can completed your friend answer? (Giving the opportunity

to answer for others student and deployment).

Student : From the opinion before, I can conclude that if the sound source and listener

are moving relative to each other (away from or close to) then the frequencies

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captured by the observer/listener is not the same as the frequency emitted by

the source.

Teacher : Exactly. A change in the observed frequency of a wave, as of sound or light,

occurring when the source and observer are in motion relative to each other,

with the frequency increasing when the source and observer approach each

other and decreasing when they move apart. This effect was discovered by the

Austrian physicist Christian Doppler in 1842. In honor of the discovery of this

effect is called the Doppler effect. Now lets look together, the animations that

have been prepared of the Doppler effects. (Concentration)

Student : Student watched animated with enthusiasm.

Teacher : There are an animation and phenomenon about the Doppler effect. Now we

are going to discuss the formula that used on the Doppler effect.

Mathematically, the Doppler effect is formulated by:

s

s

p

p fvv

vvf .

=

Where:

pf : frequency that heard by observer (Hz)

sf : acctuallies frequency by sound source (Hz)

pv : observer velocity (m/s)

sv : sound source velocity (m/s)

v : velocity of sounds (m/s)

: operation of relative velocity, (+) for opposite directional velocity and () for

same directional frequency.

Well, that was the Doppler effect formula. Now, I wanted to check your

understanding on the Doppler effect through the questions that I have been prepared.

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Student that can answer my question, then Ill give a value (+). Problem:

Ambulance moving at a speed of 20 m/s while sounding the siren has a

frequency of 1080 Hz. At that time there was someone who rides a motorcycle

is being passed to the ambulance. Motor speed of 10 m/s. What is the

frequency of the siren that motorists received if the speed of sound when it is

340 m/s? (Concentration, giving comprehension questions)

Student : Im, Miss.

Teacher : Yes, Adi please.

Student : Student write in the whiteboard.

Solutionv = 340 m/s

vs = 20 m/s,

vp = 10 m/s

fs = 1080 Hz

( )

( )HzHz

s

ms

m

fvv

vvf s

s

p

p 9901080.

20340

10340

. =

+

=

+

=

Teacher : Excellent. Give your friend applause. Until this, anybody not clearly about

the Doppler effect? (Ask for student views)

Student : Student was silent.

Teacher : Well, because no one raise your hands, I think all of you already understand

about the Doppler effect. Now, who can help me to conclude the lesson in this

meeting? (Questions of understanding)

Student : Im, Miss. The Doppler effect is a change in the frequency received by the

observer (listener) due to relative motion between the sound source to the

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listener, which can be formulated as follows: ss

p

p fvv

vvf .

= . The example

of Doppler effect in daily life as a motorcycle speeds forward, the frequency

(and pitch) of the sound waves in front of the motorcycle become higher, and

the frequency (and pitch) of the sound waves behind it become lower.

Teacher : Good job. I think the time is enough for this meeting. Do your homework,

page 60 number 1-10. If you have trouble at home, you can find me in the

office when resting time. Well, because at the beginning we started with a

praying, then right now we close with praying again. Pray is begin. Pray was

closed. Good afternoon guys. Enjoy your resting! (Giving a evaluation as a

homework and the opportunities to asking, when their find the problem at

home).

Student : Bye, Miss.

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skenario englis efek doppler sin

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