a competitor is aiming to complete a 1500-m wheel chair race in less than 4 mins. after moving at a constant speed for exactly 3.5 mins, there were still 240 m to go. what must his acceleration be for the remaining distance if he were to finish the race on time?

Question

anonymous · Answer

The competitor moved 1260m in 3.5min (210s), his speed before acceleration is:
1260m/210s = 6m/s

To determine a, use the equation:
x = v*t + 1/2*a*t²
a = 2(x - v*t)/t²

a = 2(240m - 6m/s*30s) / (30s)² = 0.133333333 m/s²

Answer:
Acceleration must be greater than 0.13 m/s²