Question

An object moves in a straight line according to the equation, x = 2 $t^3$ - 3 $t^2$ - 6t, where x is in meter and t is in second. At what time is the acceleration of the object zero?

• A. t = 0.5 s
• B. t = 1.0 s
• C. t = 2.0 s
• D. 2.5 s

Answer 1

The correct option is A

t = 0.5 s

x = 2 $t^3$ - 3 $t^2$ - 6t
v = 6 $t^2$ - 6t - 6
a = 12t - 6
equate a to zero
12t-6=0

t = 0.5 second