The distance xm travelled by a particle in time t seconds is described by the equation x = 10 + 12t2, Find the average speed of the particle between the time interval t = 2s and t = 5s
-
A.
60 ms-1 -
B.
72 ms-1 -
C.
84 ms-1 -
D.
108 ms-1
Correct Answer: Option B
Explanation
speed = (frac{dx}{dt})
(frac{dx}{dt}) = 10 + 12t2
(frac{dx}{dt}) = 24t
(frac{dx}{dt}) =24 x 3
(frac{dx}{dt}) = 72 ms-1