The applet can help you to understand speed as a rate : It is the distance travelled per unit of time.
In the applet, unit for time is seconds, and unit for distance is metres.
After you explore the applet, answer the 4 questions below the applet,
1. How far (in metres) can the red car go if it continues for 150 seconds
Total distance travelled by red car after 150 seconds
=150 x 20 = 3000 m
2. How long (in seconds) will it take the blue car to move 1200 m?
Total time taken by blue car to travel 1200 m
= 1200 /4 = 300 seconds
3. If the blue car engine is replaced with a more powerful engine, and it can travel 1200 m in 30 s, will it be faster than the red car?
Speed of blue car with new engine
= 1200/30 = 40 m/s
The red car's speed is 20 m/s.
Yes the blue car will be faster than the red car with the new engine
4. Can you write down the relationship (formula or equation) between distance (d), speed(v) and time (t) using algebraic notation ie. d, s and t ?
Distance d = __________? (in terms of v & t)
Speed v = __________? in terms of d & t)
Time t = __________? (in terms of v & d)
Distance d = v t (in terms of v & t)
Speed v = d/t (in terms of d & t)
Time t = d/v (in terms of v & d)