Here is the screen shot for the Example 3, the pulse travelled 90 cm in 1.69 seconds.
From here, we calculated the speed of the wave pulse.
Using the formula of S = D/T, the speed is equal to 90/1.69 = 53.3 cm/s, to 3 s.f.
For the next part, it is actually possible to change the speed of the wave pulse by changing the tension to 'low'.
This cause the time to get 17.02 seconds, longer than the 1.69 seconds. The new speed is equal to 90/17.02 = 2.59 cm/s to 3 s.f.
Thank you. Done by: Hao Ming and Brendon Goh (S2 - 06)