Suppose that an object moves along an s-axis so that its location is given by s(t)=t^2+4t at time t.(Here is in meters and is in seconds.)

Question

(a) Find the average velocity of the object in meters per second over the time interval t=2 to t=9 seconds.

Average velocity = ? m/s.

(b) Find the instantaneous velocity of the object in meters per second at t=5 seconds.

Instantaneous velocity = ? m/s.

Answer 1

same way as the other one but here
v = ds/dt = 2 t + 4
so at t = 5
v = 2(5) + 4 = 14 m/s

Answer 2

22
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