015 10.0 points
a subway train starting from rest leaves a
station with a constant acceleration. at the
end of 7.13 s, it is moving at 12.4062 m/s.
what is the train's displacement in the first
4.91257 s of motion?
answer in units of m.

20.996 m

Explanation:

Given:

Initial velocity,

Final velocity,

Total time taken, s.

∴ Acceleration is given as,

m/s²

Now, using Newton's equation of motion, we find the displacement.

Displacement is given as:

Plug in 0 for , 4.91257 for and 1.74 for . Solve for .

This gives,

Therefore, the train's displacement in the first 4.91257 s of motion is 20.996 m.

unlike poles attract