Question

The odometer of a car reads 2000 km at the start of a trip and 2400 km at the end of the trip. If the trip take took 8 h, calculate the average speed of the car in km/h and m/s.

Guys, I know the answer. But I don't know how the answer can be found in m/s. Do explain well, or the answer will be reported!

Answer 1

$\bold{\underline{\underline{Answer:}}}$

Average speed = 50 km/hr

Average Speed = 13.89 m/s

$\bold{\underline{\underline{Step\:-\:by\:-\:step\:explanation:}}}$

Given :-

${Initial\:reading\:of\:the\:odometer\:\bf=\:2000\:km}$

${Final\:reading\:of\:the\:odometer\:\bf\:=\:2400\:km}$

${Total\:time\:taken\:=\:8\:hrs}$

_____________________________

To find :-

${Average\:speed\:of\:the\:car\:in\:\bold{km\:per\:h}\:and\:\bold{m\:per\:second}}$

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Solution :-

$\bold{Total\:distance\:=\:Final\:distance\:-\:initial\:distance}$

$\imples$ ${Total\:distance\:=\:2400\:-\:2000}$

$\implies$ $\bold{Total\:distance\:=\:400\:km}$

${\bold{\boxed{Average\:distance\:=\frac{Total\:Distance\:travelled}{Total\:time\:taken}}}}$

Block in the values,

$\implies$$\bold{Average\:Speed\:=\:</p><p>\frac{\cancel{400}}{\cancel{8}}}$

$\implies$ $\bold{Average\:Speed\:=\:</p><p>\frac{\cancel{100}}{\cancel{2}}}$

$\bold{Average\:speed\:=\:50\:km\:per\:hour}$

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In m/s :-

$\bold{Multiply\:50\:km/hr\:by\frac{5}{18}}$

$\implies$ $\bold{\frac{5}{18}\:\times\:50}$

$\implies$ $\bold{13.89\:metre\:per\:second}$

Answer 2

Distance travelled = Final reading - Initial reading

→ Distance = 2400 - 2000

→ Distance = 400 km

Time = 8 h

Speed = Distance/Time = 400/8 = 50 km/h

In m/s:-

50 × 1000/3600

→ 50 × 5/18

→ 25 × 5/9

→ 125/9

→ 13.89 m/s