Question

the position coordinate of a moving is given by x=6+18t+9t² where x is in meter and t is in second. what is the velocity at t=2sec​

Answer 1

velocity is slope of distance curve or line in distance - time graph

so v = dx/dt = 0 + 18 + 18t

= 18 + 18t

so at t = 2s

v = 18+18×2

= 18+36

= 54