1. Chiang Mai Rally
Chiang Mai Rally Speed
Episode 2:
Speed

2. Objectives: Chiang Mai Rally Speed Understand the concept of speed.
Carry out a scientific investigation on the effect of the height of a slope on the speed of a car.
Calculate the speed of a car from data collected and data supplied.
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3. Engage
Thank you for presenting your suggested routes to the committee. We will need some further advice from you before we can make a decision.
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4. Chiang Mai Rally Speed What is speed? How can we calculate
Engage
What is speed?
How can we calculate
the speed of a car?
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5. Chiang Mai Rally Speed speed distance time =
Engage
The speed of an object is the distance the object moves per unit of time. You can calculate speed by dividing the distance covered by the time taken to cover it.
speed
distance
time =
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6. Total distance (kilometers)
Engage
These were the results for the fastest cars on races during our programme
Rally Programme
Total distance (kilometers)
Time
(hours)
Rally of Thailand 2011
218
2.42
Asia Cross Country Rally 2011 Overall
2200
10.35
Rally of Thailand Championship 2011 Venue 2 73
0.37
Chiang Mai Rally Speed
What were the average speeds of each car?
SS1 6

7. How does the steepness of the road affect the speed of a car? Any ideas?
And why do you think the rally organisers need to know this?
Explore
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8. Explore
Plan and carry out a scientific investigation to find out how the slope of a road affects the speed of the rally car. Use the scientific investigation planning sheet for help. Prepare to present the outcome of your investigation to me and the committee.
Chiang Mai Rally Speed
SS2 8

9. Explore
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10. Explain
Explain what your investigation results show about the effect of the slope on the car speed. And are there any other factors we need to think about to keep the drivers (and spectators) safe?
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11. Elaborate
We tested three of your routes from Chiang Mai to Chiang Rai. I’ve got the results here for you.
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12. A B C Chiang Mai Rally Speed Elaborate
Route A: total distance 265 kilometers Time taken to complete the route = 5 h 30 m
Route B: total distance 200 kilometers Time taken to complete the route = 4 h
Route C: total distance 335 kilometers Time taken to complete the route = 8 h 15 m
What was the average speed of the car on each route?
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13. Chiang Mai Rally Speed Elaborate 48.18km/h 50km/h 40.61km/h
Route A: total distance 265 kilometers Time taken to complete the route = 5 h 30 m
Route B: total distance 200 kilometers Time taken to complete the route = 4 h
Route C: total distance 335 kilometers Time taken to complete the route = 8 h 15 m 13

14. Evaluate
Which route do you think is the best route for this year’s rally? And which route may be too dangerous? Give reasons for your choices using ideas from your investigation.
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15. Chiang Mai Rally Speed Contact the Inspiring Science team at
Contact Details
Contact the Inspiring Science team at
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