Question

express the following speeds in meter per second 72km per hour

Answer 1

Heya!!!

There are two ways to convert 72 km/h to m/s.

1st method:

72 km/h =( 72 × 1000) / 60 × 60

= 72000/3600

= 20 m/s

2nd method:

72 km/h = 72 × 5/18

= 4×5

= 20 m/s

Hope it helps u.
-)
:)

Answer 2

Express the 72 $\dfrac{km}{hr}$ is 20 $\dfrac{m}{sec}$.

Step-by-step explanation:

We have,

72 $\dfrac{km}{hr}$

To express the speed in meter per second = ?

We know that,

1 km = 1000 m and

1 hr = 3600 sec

∴ 72 $\dfrac{km}{hr}$

= 72 $\dfrac{1000m}{3600sec}$

$= 72\times \dfrac{1000}{3600}\dfrac{m}{sec}$

$=72\times \dfrac{10}{36}\dfrac{m}{sec}$

$=2\times 10\dfrac{m}{sec}$

= 20 $\dfrac{m}{sec}$

Trick:

Convert $\dfrac{km}{hr}$ to $\dfrac{m}{sec}$

Multiply by $\dfrac{5}{18}$

72 $\dfrac{km}{hr}$

= 72 × $\dfrac{5}{18}$ $\dfrac{m}{sec}$

= 4 × 5 = 20 $\dfrac{m}{sec}$

Hence, to express the 72 $\dfrac{km}{hr}$ is 20 $\dfrac{m}{sec}$.