The speed of the train with time is given on a speed time graph
obtained from a past questions website drawn and attached here.
Correct response:
- The time the train took to completely cross the bridge is approximately 46.26 seconds.
Method used for the calculation
Given:
Length of the train = 220 m
Time at which the train crossed the bridge = 9:30
Length of the bridge = 1,400 m
The plot of the graph of the motion of the train obtained from a past papers website and created with MS Excel is attached;
From the attached graph, we have;
The speed of the train at 9:30 = 126 km/h
Required:
The time it took the train to completely cross the bridge.
Solution:
- [tex]Time = \mathbf{\dfrac{Distance}{Velocity}}[/tex]
[tex]126 \, km/h = 126 \, km/hr \times \dfrac{1,000 \, m}{1 \, km} \times \dfrac{1 \ hr}{3,600 \, s} = \mathbf{ 35 \, m/s}[/tex]
Therefore, the time it took the train to completely cross the bridge is given as follows;
Distance traveled = 1,400 m + 220 m = 1,620 m
- [tex]Time, \, t = \mathbf{\dfrac{1,620 \, m}{35 \, m/s}} = 46.\overline{285714} \, s \approx 46.29 \, s[/tex]
The time it took the train to completely cross the bridge is t ≈ 46.29 s
Learn more about velocity and speed here:
https://brainly.com/question/11315548
