Question

Express each of the following in m s -1 (a) 1 km/h (b) 18 km/min

February 16, 2024

Answer

(a) 1 km h^-1 = ${1\ km\over1\ h}$

= ${1\times 1000\ m\over60 \times 60\ s}$

= 0.278 m s^-1

(b) 18 km min^-1 = ${18\ km\over 1\ min}$

= ${18 \times 1000\ m\over60\ s}$

= ${18 \times 10\ m\over 6}$

= 300 m s^-1

Hence, 18 km h^-1 is equal to 300 m s^-1.

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