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Physics
How do we calculate the average speed of an object?

The bus route from Almaty to Astana is a distance of 1214 km. The duration of the bus ride
is 19 hours. The average speed is calculated using this equation:

average speed = total distance covered / total time taken
v av = 1214 km / 19 hours = 63.9 km/h

In SI units: 63.9 km/h x (1000 m/3600 sec) = 17.75 m/s 18 19
textbooks nis edu kz
What do you think could happen during the journey to 12
prevent the bus driver from keeping a constant speed? 11 14 17
13 16
15
10 3
Average velocity 8 9 4 1
We must remember that speed is different from velocity. 2
7
When we are considering velocity, which is a vector 5
quantity, we need to think about displacement, which is 6
also a vector quantity. Displacement is concerned with Plan of the Formula 1 racetrack at Sochi Autodrom,
the initial position and the final position of an object. Russia

In the 2015 Formula 1 Russian Grand Prix, in his fastest lap, Sebastian Vettel drove the total
distance of 5.848 km in 1 minute and 40.071 seconds.
You will notice from the plan above that this racing circuit is a closed loop. That means drivers
always return to their original starting place after each lap. So although Sebastian Vettel had
an average speed of around 58 m/s for his fastest lap, his average velocity for that lap was
always zero, because his total displacement in the lap was zero. This is true for every lap!

OVER TO YOU!

1. A dog walks around at 1.5 m/s 3. Determine the average speed and the average velocity of this
then breaks into a sprint to cyclist over 3 minutes.
chase a ball at 5 m/s. It takes
A t = 0 min B t = 1 min
it 3.4 s to do all this. How far
does the dog travel?
40 m 100 m 40 m
2. A triathlete swims 3860m in
4 hours, then cycles 180.2
km in 540 minutes, then runs C t = 2 min D t = 3 min
42.2 km in 10 hours. After
each stage he has a rest and 4. Imagine you are an SUV driver participating in the 2014 Steppe
changes his clothes, and each Wolves Kazakhstan Rally Cup. The total distance is 314 km,
of these breaks lasts about 199 km of which cover special high-speed tracks. The rally
50 minutes. Calculate his course is not a closed loop like the Formula 1 example. How
average speed in m/s. do you think the motion and speed will change with time?

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