Question

Question 1
Which speed is greater 72 m/s or 90 km/h?Justify your answer with
necessary calculations,

Answer 1

Answer:

72m/s is greater than 90km/hr

Explanation:

So we need to convert 90km/hr to m/s to find which is greater,

Conversion

For Km/hr to m/s is

$\frac{5}{18}$×Km/hr

⇒ $\frac{5}{18}$×90 = 25m/s

By comparison we can say that

             72m/s > 25m/s

         ∴ 72m/s > 90km/hr

Answer 2

Explanation:

change 90 km/h into m/s

90× 5÷18= 25m/s

hence 72m/s is greater than 90 km/h

1 km= 1000 m

1h= 3600 seconds

1000÷3600=5/18