(a) A race car moves such that its position fits the relationship x = (5.5 m/s)t + (0.65 m/s³)t³ where x is measured in meters and t in seconds.

(b) Determine the instantaneous velocity of the car at t = 3.8 s, using time intervals of 0.40 s, 0.20 s, and 0.10 s. (In order to better see the limiting process keep at least three decimal places in your answer.)

Δt = 0.40 s	m/s (Use the interval from t = 3.60 s to 4.00 s.)
Δt = 0.20 s	m/s (Use the interval from t = 3.70 s to 3.90 s.)
Δt = 0.10 s	m/s (Use the interval from t = 3.75 s to 3.85 s.)

 

x (m) 180- 160 140 120 100 80 60 40 20 t (s) 6.00 1.00 2.00 3.00 4.00 5.00