A car travels a distance of 15 km in 20 minutes. Find the speed of the car in $$ m s^{-1} $$
Speed of car in $$ m s^{-1} $$
Convert 15 km into meters
1 km = 1000 m
15 km = $$ 1000 \times 15 $$ = 15000 m ......(i)
Convert minutes into seconds
1 minutes = 60 sec.
20 minutes = $$ 60 \times 20 $$ = 1200 sec ........ (ii)
Speed of car = $$ \dfrac{distance}{time} $$
Speed of car = $$ \dfrac{15000 m}{1200 sec} $$ = $$ 12.5 m s^{-1} $$