Question

A boy runs straight in the east direction He travels 100m in 20s.Calculate his average speed and average velocity. Are both equal

Answer 1

A boy runs straight in the east direction He travels 100m in 20s

Formula Applied :

Average speed is defined as total distance travelled per total time

$\bigstar\ \; \sf \pink{A_{Speed}=\dfrac{T_{Distance}}{T_{TIme}}}$

Average velocity is defined as displacement per time

$\bigstar\ \; \sf \blue{A_{Velocity}=\dfrac{Displacement}{Time}}\\\\\bigstar\ \; \sf A_{Velocity}=\dfrac{\Delta x}{\Delta t}$

Solution :

For a straight line moving object , distance travelled is equals to displacement .

You know why ?

Displacement is defined as the shortest distance b/w two points , which is in straight line . So , In straight line displacement is equals to distance travelled .

For Average Speed ,

Total distance = 100 m

Total time = 20 s

$\to \sf A_{Speed}=\dfrac{100}{20}\\\\\to \sf \green{A_{Speed}=5\ m/s}\ \; \bigstar$

For Average Velocity :

Displacement = 100 m

Time = 20 s

$\to \sf A_{Velocity}=\dfrac{100}{20}\\\\\to \sf \red{A_{Velocity}=5\ m/s}\ \; \bigstar$

Displacement and distance would be same , when bodies are travelling in straight line . Then , Average velocity and speed , would be same . This is the case for example .

Answer 2

$\large{\sf{\underline{\underline\pink{Given:-}}}}$

• Total Distance = 100 m

• Time taken = 20 seconds

$\large{\sf{\underline{\underline\green{To\:Find:-}}}}$

• His average speed and average velocity.

$\large{\sf{\underline{\underline\pink{Solution:-}}}}$

To find average speed :-

➩  Average speed = Distance/Time

➩  100/20

➩  5 m/s

To find average velocity :-

➩  Average velocity = Distance/Time

➩  100/20

➩  5 m/s

Hence, Average speed and Average velocity are both equal.