Question

The odometer of car read 200 km at the start of trip and 240 km at the end of the trip. If the trip took 8 hr, find the average speed of the car in km/hr and in m/s.​

Answer 1

Explanation:

Total distance covered = 240 - 200 = 40 km.

Total time taken = 8 hr.

avg speed = total distance covered / total time

= 40km / 8hr

= 5 km/hr

In m/s ,

avg speed = 5 . 5/18 = 25/18 = 1.39 m/s .

Answer 2

Odometer :

• An Odometer is a device that is used to measure the distance travelled by the automobile

Given :

• Initial reading = 200km

• Final reading = 240 km

• Total time taken to complete the trip = 8 hours

Aim :

• To find the Average speed of the car in km/h and m/s

Solution :

Distance travelled by the car : (Final reading) - (Initial reading)

⇒ 240 km - 200 km

⇒ 40 km

∴ In 8 hours, the car travelled a distance of 40 km.

Average Speed :

• The average speed of an object is calculated by the formula : Total distance travelled by the object divided by total time taken by the object.

Average Speed in km/hr :

$\implies \sf Average\:Speed = \dfrac{40}{8}$

Reducing to the lowest terms,

$\boxed{\implies \sf 5km/hr}$

Average Speed in m/s :

We know that,

→ 1km = 1000m

40km = 40 × 1000 → 40000m

→ 1 hour = 3600 seconds

8 hours = 8 × 3600 → 28800 seconds

$\implies \sf \dfrac{40000}{28800}$

Reducing to the lowest terms,

$\boxed{\implies \sf 1.3\overline{8}}$

∴ Average speed of the car in km/hr is 5km/hr and in m/s is 1.38888..m/s

More formulas :

• v = u + at
• s = ut + at²/2
• v² = u² + 2as