A train departs from its station at a constant acceleration of 5 m/s2. What is the speed of the train at the end of 20s?

v = at

40 To find the speed of the train at the end of 20 seconds, we can use the equation of motion:

v = u + at

where:
- v is the final velocity (speed) of the train
- u is the initial velocity of the train (which is usually 0 for a train starting from rest)
- a is the acceleration of the train
- t is the time taken

In this case, the initial velocity (u) is 0 because the train starts from rest. The acceleration (a) is given as 5 m/s^2, and the time (t) is 20 seconds. Let's substitute these values into the equation:

v = 0 + (5 m/s^2)(20 s)
v = 0 + 100 m/s
v = 100 m/s

Therefore, the speed of the train at the end of 20 seconds is 100 m/s.