Question

a school boy covers a 3km distance in 5 min. calculate speed- a)cm/s b)km/h

Answer 1

a).given distance =3km=3000m=300000cm

time =5min=300sec

now, speed =300000/300=1000cm/s

b).distance =3km

time=5min=5/60hr=1/12 hr

now, speed=3(12)=36kmph


hope this helps !!!

Answer 2

Given,

Distance = 3 kilometres

= 3 * 100000 centimetres

= 300000 centimetres

Time = 5 minutes

= 5 * 60

= 300 seconds

= 5/60 hour

Calculation,

a) Speed in cm/s = Distance in cm / Time in sec

= 300000 / 300

= 3000 / 3

= 1000 cm/sec Ans.

b) Speed in km/hr = Distance in km / Time in hr

= 3 / (5/60)

= (3 * 60) / 5

= 180 / 5

= 36 km/hr Ans.