Question

An athlete takes 2.0sec to reach his max. Speed of 18.0km/h. What is the magnitude. Of his average acceleration.

Answer 1

Answer on Question #39492, Physics, Mechanics | Kinematics | Dynamics

Question:

An athlete takes 2.0sec to reach his max. speed of 18.0km/h. What is the magnitude of his average acceleration?

Answer:

If a body is having an initial velocity $v_{i}$ at time interval $t_{i}$ and it attains final velocity $v_{f}$ after some time $t_{f}$ then its average acceleration formula is given by

$$a = \frac {v _ {f} - v _ {i}}{t _ {f} - t _ {i}}$$

Where $v_{i}$ is the initial velocity, $v_{f}$ is the final velocity, $t_{i}$ is the initial time, $t_{f}$ is the final time.

Therefore:

$$a = \frac {1 8 \frac {k m}{h}}{2 s} = \frac {1 8 \frac {m}{s}}{3 . 6 \cdot 2 s} = 2. 5 \frac {m}{s ^ {2}}$$

Answer: $2.5\frac{m}{s^2}$