Question

With an average acceleration of -0.50m/s^2, how long will it take a cyclist to bring a bicycle with an initial speed of 13.5m/s to a complete stop?

Answer 1

given that

acceleration = - 0.50 m/s^2

v = 13.5 m/s

so final speed will become zero after it completely stop

so here we can use kinematics

$v_f = v_i + at$

$0 = 13.5 - 0.50 * t$

$13.5 = 0.5 * t$

$t = 27 s$

so cycle will completely stop after t = 27 s