A runner completes a circular path of 1000 m in 2 min 5 s. What is its

1.	A runner completes a circular path of 1000 m in 2 min 5 s. What is its average speed and average velocity?
Answer» Total distance travelled by the runner in 2 min 5 s = 1000 m Total time of the whole journey t = 2 min 5 s or t = (2 × 60) s + 5 s = 120 s + 5 s = 125 s Therefore average speed of the runner, \(\vec{v}=\frac{s}{t}=\frac{1000}{125}\) = 8m/ s v or \(\vec{v}\) = 8 m/s Since, the runner runs for one complete one cycle, therefore its initial and final positions coincide with each other. Thus, the displacement becomes zero i. e, \(\overrightarrow{\Delta x}\) = 0 (zero) Hence, average velocity \(\vec{v}=\frac{\overrightarrow{\Delta x}}{\Delta t}=\frac{0}{125}=0\) or \(\vec{v}\) = 0 (zero)

A runner completes a circular path of 1000 m in 2 min 5 s. What is its average speed and average velocity?

Answer»

Total distance travelled by the runner in 2 min 5 s = 1000 m
Total time of the whole journey t = 2 min 5 s
or t = (2 × 60) s + 5 s
= 120 s + 5 s = 125 s
Therefore average speed of the runner,
\(\vec{v}=\frac{s}{t}=\frac{1000}{125}\) = 8m/ s v
or \(\vec{v}\) = 8 m/s
Since, the runner runs for one complete one cycle, therefore its initial and final positions coincide with each other.
Thus, the displacement becomes zero i. e,
\(\overrightarrow{\Delta x}\) = 0 (zero)
Hence, average velocity

\(\vec{v}=\frac{\overrightarrow{\Delta x}}{\Delta t}=\frac{0}{125}=0\)
or \(\vec{v}\) = 0 (zero)

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