A 400 g air-track glider collides with a spring at one end of the track.?

(Delta v)/ (Delta t) = acceleration so F (glider) = m * a = F (spring) = -kx = 36 at x(max) and v = 0 therefore, m*Delta(v)/36 = Delta (t) = .4 * 3 / 36 = .0333 this is only half the time though so t(total) = .0666 seconds.

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