Question

The position of an object
moving along x-axis is given by x = a + bt^2 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

Explanation:

given x= a+ bt² and a=8.5m and b=2.5m/s²

thus, x=8.5 + 2.5t²

Now, velocity will be

v= dx/dt

v= d(8.5 + 2.5t²)/dt

v= 5t m/s

Now,

velocity at t= 0s will be, v= 5(0) = 0m/s

velocity at t = 2s will be, v= 5(2) = 10m/s

velocity at t= 4s will be , v= 5(4) = 20m/s

so avg velocity is,

(20+10)/2

= 15m/s