Question

2) A Soldier marches at speed of 2m/s. what distance will he
coners in one hour?
Ans.speed of soldier = 2m/s
= 2 x 18km/5 hr -7.2 km/hr

Time taken = 1 hr
distance= speed×time=7.2 km/hr× 1 hr
= 7.2 km

just tell me that from where do the 18km/5hr came in speed of soldier​
I shall mark brainliest if u answer my question

Answer 1

TO CONVERT SPEED IN M/S TO KM/HR WE MULTIPLY IT FROM 3600SECONDS / 1000 KM

SO THEY CANCEL OUT AND BECOME 18/5

LIKE THIS

(3600/1000)÷200

= 18/5

YOU CAN ALSO DO THIS IN THIS METHOD ALSO

SPEED = 2M/S

TIME = 1HR OR 60 MINUTES OR 3600 SECONDS

DISTANCE = SPEED × TIME

SO,

DISTANCE = 2×3600

= 7200METRES OR 7.2 KM IN ONE HOUR

BOTH METHODS WILL GIVE SAME ANSWER

MARK AS BRAINLIEST IF YOU LIKE MY ANSWER ......

Answer 2

Explanation:

SEE THAT 18/5 is multiplied to 2m/s for getting

its value in km/hr

LET ME DERIVE IT

$1 \frac{m}{s} = \frac{ \frac{ \frac{1}{ {10}^{3}}km }{1} }{3600} hr \: \: \: \\ as \: 1m = {10}^{ - 3} km \: and \: 1sec = \frac{1}{3600} hr \\ \: so \: on \: simplifying \: 1m {s}^{ - 1} = \frac{18}{5} km \: {hr}^{ - 1}$

so we multiply 18/5 for converting m/s to km/hr