The odometer of a car reads 57321.0 km when the clock shows the time 08:30 AM. What is the distance moved by car, if at 08:50 AM, the odometer reading has changed to 57336.0 km? Calculate the speed of the car in km/min during this time. Express the speed in km/h also.

AcademicPhysicsNCERTClass 7

Given:

The odometer of a car reads $57321.0\ km$ when the clock shows the time $08:30\ AM$.


To do:

To find the distance moved by car if at $08:50\ AM$, the odometer reading has changed to $57336.0\ km$.

Solution:

At 8:30 AM-

Reading of odometer of the car $=57321.0\ km$

At 8:50 AM-

Reading of odometer of the car $=57336.0\ km$

Therefore, the distance traveled by car $=57336.0\ km-57321.0\ km$

$=15\ km$

Here time taken $=8:50-8:30=20\ minutes$

So, speed $=\frac{distance}{time}$

$=\frac{15\ km}{20\ minutes}$

$=0.75\ km/minute$

We know that $1\ km/minute=60\ km/h$

So, speed of the car in $km/h=0.75\times60$

$=45\ km/h$

Therefore, the distance traveled by car $=15\ km$.

Speed of the car $=0.75\ km/minute$

In $km/h$, speed of the car $=45\ km/h$

raja
Updated on 10-Oct-2022 13:25:51

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