Question

Un tren a parcurs distanta de 75 km dintre 2 statii in timp de 50 min. Care este viteza medie a trenului exprimata in km/h si m/s?

Va rog, repede, dau coroana​

Answer 1

$\bf 75\, km = 75 \cdot 1000\, m = 75000\,m$

$\bf 50\, min = 50 \cdot 60\, s = 3000\,s$

$\bf v=\dfrac{\Delta d}{\Delta t} =\dfrac{75000m}{3000s} = \boxed{\boxed{\bf 25\dfrac{m}{s}}}$

$\bf v=25\dfrac{m}{s} =25:\dfrac{km}{h} =25:\dfrac{1000m}{3600s}$

$\bf v=25 \cdot \dfrac{3600}{1000} =\dfrac{25 \cdot 36}{10} =\dfrac{900}{10}\dfrac{km}{h}$

$\bf \implies \boxed{\boxed{\bf v=90\dfrac{km}{h} }}$

Bafta! :)

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