Question

Example 3.2 The position of an object
moving along x-axis is given by x = a + bt
where a = 8.5 m, b = 2.5 m s-2 and t is
measured in seconds. What is its velocity at
t=0 s and t = 2.0 s. What is the average
velocity between t = 2.0 s and t = 4.0 s?​

Answer 1

X = a + bt^2

v = 2bt

Velocity at t = 0 is 0

Velocity at t = 2s is = 2*2.5*2 = 10 m/s

At t = 2s

x = 8.5 + 2.5*2^2

x = 18.5m

At t = 4s

x = 8.5 + 2.5*4^2

x = 48.5m

Average velocity = (48.5 - 18.5) / 2 = 18m/s