Question

♠ QUESTION :-
The odometer of a car reads 2000 km at the start of the trip and 2400 km at the end of the trip. If the trip took 8 h, calculate the average speed of the car in km $h^{-1}$ and m $s^{-1}$.​

Answer 1

♣ Question :-

The odometer of a car reads 2000 km at the start of the trip and 2400 km at the end of the trip. If the trip took 8 h, calculate the average speed of the car in km $h^{-1}$ and m $s^{-1}$.

♣ Answer :-

Distance covered by the car,

s = 2400 km - 2000 km = 400 km

Time elapsed, t = 8 h

Average Speed of the car is,

$V_av$ = $\frac{s}{t}$ = $\frac{400 km}{8 h}$

= 50 km $h^{-1}$

= 50$\frac{km}{h}$ × $\frac{1000 m}{1 km}$ × $\frac{1 h}{3600 s}$

= 13.9 m $s^{-1}$

$\Rightarrow$ The average speed of the car is 50 km $\sf{ h^{-1}}$ or 13.9 m $\sf{s^{-1}}$.

Answer 2

Answer:

Initial odometer reading=2000km

Final odometer reading=2400km

Total distance= Final distance- Initial distance

=2400-200=400km

Total time=8h

Average speed =?

Formula to be used :

Average speed= Total Distance/Total time

Average speed in Km/hr:

Average speed=400/8

=50 km/hr

Average Speed in m/s:

1km/hr=5/18 m/s

∴50km/hr=50x5/18=250/18=13.88m/s