Suppose a particle responds to this equation of motion: s = t2 - 5t + 6
a) find the velocity at two seconds and three seconds
b) find the acceleration
c) find the total distance covered after 3 seconds
s = t2 - 5t + 6
v = ds/dt = 2t - 5
a = dv/dt = 2
The Attempt at a Solution
ai) 2t - 5 = 4 - 5 = -1
aii) 2t - 5 = 6 - 5 = 1
(everything is fine here)
b) a = 2
c) The equation given above is for position, since it uses velocity. Is it actually possible to find the distance covered from the displacement?
I also tried finding the position at t = 1, t = 2 and t = 3 to find the distance.
at t = 1, s = 2
at t = 2, s = 4 - 10 + 6 = 0
at t = 3, s = 9 - 15 + 6 = 0
How is it possible that the displacement is 0 twice consecutively if the velocity is non-zero? Isn't that impossible?
I was actually going to calculate the displacement each time then add all together. The book had also already given an answer: 6.5m, although i'm not sure of how they got that.
Thanks for any answers.