(GLB) Motion with Constant Speed

Open Ended

What happen when we turn on the cruise control button in the car?

Apa yang terjadi apabila kita menekan tombol cruise control pada mobil?

Open Ended

Based on the video, what is the meaning of the car moves in a certain speed?

“Apa maksud dari mobil bergerak dengan kecepatan tertentu pada video?”

GLB (Motion at Constant Speed)

​Some text here about the topic of discussion.

Kompetensi Dasar

​KD 3.4 &4.4

​3.4. Menganalisis besaran-besaran fisis pada gerak lurus dengan kecepatan konstan (tetap) dan gerak lurus dengan percepatan konstan (tetap) berikut penerapannya dalam kehidupan sehari-hari misalnya keselamatan lalu lintas.

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​4.4. Menyajikan data dan grafik hasil percobaan untuk menyelidiki sifat gerak benda yang bergerak lurus dengan kecepatan konstan (tetap) dan bergerak lurus dengan percepatan konstan (tetap) berikut makna fisisnya.

GLB (Motion with constant speed)​

• Students can analyze the physical quantities of motion of the object at a constant speed correctly.

• Students can interprete the data and graph of motion (distance-time graph) of object at constant speed​ correctly.​

GLB

​Learning Objectives

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​Benefits we study motion?

Constant means "unchanging over time."

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​"Constant"

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Speed is the rate that a certain distance is covered over time.

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Speed is scalar.​ It tells us only the magnitude of how fast an object is moving.

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The SI unit for speed is meters per second (m/s)​

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Speed

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Multiple Choice

The distance an object moves in a unit of time

• speed

• force

• velocity

• acceleration

• position

Multiple Select

Which two formulas show the correct formula for calculating speed?

• distance/time 

• distance x time

• distance x distance 

• time/distance 

• time

Multiple Choice

A bus carrying students to a band concert traveled 90 km in 2 hours. What was the speed of the bus?

• 45 km/h

• 45 h/km

• 180 km/h

• 180 h/km

• 36 km/h

Multiple Choice

The speed and direction of a moving object is its -

• velocity

• acceleration

• force

• distance

Are speed and velocity the same thing?

NO!

Velocity is the rate of displacement that is covered over time.

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Velocity is a vector.​ It tells us both the magnitude (speed) and direction of an object's motion.

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The SI unit for velocity is meters per second (m/s)​

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Velocity

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Constant speed and velocity

So if constant means "unchanging"...

Then constant speed or constant velocity means that an object's speed or velocity is not changing over time.

Any changes in an object's position over time can be graphed with position on the y-axis and time on the x-axis.

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​Position vs time graph

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The slope of a position vs time graph for an object experiencing constant motion is linear (a straight line).

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​Position vs time graph

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Describing the Motion

Object is moving in a positive direction ​away from the origin with a constant positive velocity.

​Object is at rest at a positive position away from the origin.

​Object is moving in a negative direction towards the origin with a constant negative velocity.

Multiple Choice

When is the object moving with a negative velocity towards the origin?

• 15 - 40 seconds

• 15 - 30 seconds

• 40 5

• 55 seconds

Multiple Choice

Which time segment shows the object at rest?

• 10-15 seconds

• 30 seconds

• 15-40 seconds

• 55 seconds

Multiple Choice

What does this graph represent?

• Constant Speed

• Acceleration

• Not moving

Multiple Choice

What does this graph represent?

• Constant speed

• Acceleration

• Not moving

Multiple Choice

Which person moved the fastest in 3 seconds?

• biker

• runner

• walker

• they are all moving equally

• runner and walker