Question

An athlete completes a race in 12 seconds, and his team plots his v-t graph. Find out the length of the race and maximum acceleration achieved by the athlete using the graph.

• A. 80 𝑚, 4 𝑚𝑠−2
• B. 96 𝑚, 2 𝑚𝑠−2
• C. 80 𝑚, 2 𝑚𝑠−2
• D. 96 𝑚, 4 𝑚𝑠−2

Answer 1

The correct option is C 80 𝑚, 2 𝑚𝑠−2

• Length of the race = Displacement = Area under the v-t graph

• Area = A1 + A2 = ½ × 8 × 4 + 8 × 8 = 80 m

Maximum acceleration = Maximum slope = (8 - 0) ÷ (4 - 0) = 2 ms-2